hanisah manshor | International Islamic University Malaysia (original) (raw)

Papers by hanisah manshor

Journal of Advanced Research in Applied Sciences and Engineering Technology

The preference for a ceramic matrix composite, in many applications, is due to its allowance for ... more The preference for a ceramic matrix composite, in many applications, is due to its allowance for alterations, with regards to the filler or reinforcement used. Among the well-known ceramic matrix composites, is the carbon nanotube reinforced ceramic matrix composite. This ceramic composite, which possesses excellent properties, is used exclusively for high-end applications. However, other than the fact that this composite is prone to damage, in a high temperature environment during the sintering process, its use also comes at a high cost. Among the solutions to these drawbacks, is the introduction of carbon into the ceramic composite, through the chemical vapour infiltration (CVI) process. Initially, pyrolysis of biomass is applied on the empty fruit bunch (EFB), for the generation of tar vapour. Pyrolytic carbon is then produced through secondary reaction, during contact with the ceramic surface. The findings, derived from previous studies, indicate that the physical properties of ...

AIP Conference Proceedings

The development of advanced cutting tools for the industrial sectors required materials that can ... more The development of advanced cutting tools for the industrial sectors required materials that can provide a high performance in term of its microstructure, hardness and fracture toughness. Therefore, continuous improvement of ZTA cutting tool is aimed in this research. The purpose of this study is to investigate the effect of single-walled nanotubes (SWNT) addition on physical and microstructural properties of ZTA cutting tools. Ceramic composites with compositions of 80 wt.% of Al2O3 and 20 wt.% YSZ were added with varied amount of SWNT which are 0.05, 0.1, 0.3 and 0.5 wt.%. The SWNT was soaked in 20 mL ethanol under ultrasonic condition for 1 hour and mixed with the composition. These batch of compositions were ball milled for 24 hours before properly dried and powdered. The powder is then pressed into round-shaped cutting inserts mold by the uniaxial pressure of 100 MPa. The prepared samples were sintered at 1600 °C for 4 hours soaking time under pressureless condition. The bulk density and porosity of the sintered sample was identified and SEM images are used to analyze the microstructure of the sample. The effect of SWNT addition was observed on the bulk density, porosity, and microstructure of the sintered samples. The results indicated that the addition of 0.1 wt.% of SWNT to the composite, the highest bulk density of 3.987 g/cm3 was obtained. The small addition of SWNT (< 0.1 wt.%) formed a bridging effect with the Al2O3 and ZrO2 particles. The maximum value of SWNT can be added is 0.1 wt.% where further additions of the SWNT to the composition will reduce the properties of the ZTA cutting tool.The development of advanced cutting tools for the industrial sectors required materials that can provide a high performance in term of its microstructure, hardness and fracture toughness. Therefore, continuous improvement of ZTA cutting tool is aimed in this research. The purpose of this study is to investigate the effect of single-walled nanotubes (SWNT) addition on physical and microstructural properties of ZTA cutting tools. Ceramic composites with compositions of 80 wt.% of Al2O3 and 20 wt.% YSZ were added with varied amount of SWNT which are 0.05, 0.1, 0.3 and 0.5 wt.%. The SWNT was soaked in 20 mL ethanol under ultrasonic condition for 1 hour and mixed with the composition. These batch of compositions were ball milled for 24 hours before properly dried and powdered. The powder is then pressed into round-shaped cutting inserts mold by the uniaxial pressure of 100 MPa. The prepared samples were sintered at 1600 °C for 4 hours soaking time under pressureless condition. The bulk density and porosity of ...

Materials Science Forum, 2020

This paper investigated the performance of ZTA cutting tool with the addition of different partic... more This paper investigated the performance of ZTA cutting tool with the addition of different particle size of MgO additive. Therefore, the objective of this research is to compare the effects of machining parameters on tool wears of ZTA cutting tools added with micro and nanoparticle of MgO. The experiments were conducted using BridgePort-Romi Powerpath CNC machine using a tool holder Sandvik Coromant (CoroTurn CCLNR 164D-4) to hold the cutting tools properly. The parameters are set up as cutting speeds used between range 354 to 472 m/min, feed rate from 0.1 to 0.5 mm/rev with a constant depth of cut of 0.2 mm. Three types of wear were analyzed which are flank wear, crater wear and tool chipping. Flank wear and crater wear images captured using measuring microscope (NIKON MM-400/L) and the crater wear areas are analyzed using MatLab programming software. Tool chipping is observed via SEM (JEOL JSM-5600). The experimental result shows that flank wear and crater wear increase when cutti...

Key Engineering Materials, 2022

This study examines the effect of adding various amount of polyvinyl alcohol (PVA) from 1 wt. % t... more This study examines the effect of adding various amount of polyvinyl alcohol (PVA) from 1 wt. % to 5 wt. % as function to produce porosity of the microstructure on Zirconia-Toughened Alumina (ZTA). Porosity is required in this study which aims to increase the efficiency of carbon infiltration on the porous composite through chemical vapor infiltration (CVI). Moreover, carbon production from empty fruit bunch (EFB) was used as a reinforcement on ceramic composites in this system. The microstructure of samples was characterised by using scanning electron microscopy (SEM). The density shows the lowest at 2.864 g/cm3 when the percentage of binder is increased at 4wt.% of PVA without carbon infiltration but shows the highest density value which is 4.107 g/cm3 after carbon is infiltrated. Vickers hardness was used to identify the hardness of samples. It was found that ZTA composite with infiltrated carbon has better hardness (2053HV) with addition of 4wt.% of PVA. However, firing shrinkag...

Key Engineering Materials, 2022

The ZTA-TiO2-Cr2O3 ceramic cutting tool is a new cutting tool that possesses good hardness and fr... more The ZTA-TiO2-Cr2O3 ceramic cutting tool is a new cutting tool that possesses good hardness and fracture toughness. Yet, the performance of the ZTA-TiO2-Cr2O3 cutting tool is still unknown and needs further study. In this research, the comparison of the ZTA-TiO2-Cr2O3 and Kennametal ceramic cutting tool is investigated. The turning process by using ZTA-TiO2-Cr2O3 and Kennametal commercial ceramic cutting tools is performed on the Bridgeport ROMI PowerPath CNC lathe machine. The parameters utilized are spindle speed in the range of 907 to 1543 rpm, feed rate from 0.08 to 0.22 mm/rev, and depth of cut of 0.2 mm. Analysis of the flank wear and crater wear were performed by using an optical microscope (NIKON MM-4001L), while the chipping area was observed by scanning electron microscopy, SEM (JEOL JSM-IT100). The surface roughness of the machined surface is measured via portable surface roughness (Mahr MarSurf M3000C). The comparison between the cutting tool produced in this research and...

Journal of Engineering and Science Research, 2021

The electrochemical and corrosion behaviour of Zn-20Sn and Zn-0.50Ag alloys in dishwasher deterge... more The electrochemical and corrosion behaviour of Zn-20Sn and Zn-0.50Ag alloys in dishwasher detergent solution was investigated by Tafel plot and characterized X-ray diffraction (XRD) and Scanning Electrode Microscope (SEM). The measurements were conducted using different composition of elements addition (Ag: 0.03%, 0.27% and 0.50%. Sn: 1%, 8%, and 15%) under the same experimental conditions. The results showed that the addition of Ag led to decreased corrosion rate compared to Sn addition. The corrosion potential for Zn alloy with Ag addition are shifted towards more noble values compared to Zn alloys with Sn addition . By adding Ag, the current density is decreased and thus reducing the hydrogen evolution rate. The corrosion layer formed on Zinc sample in dishwasher detergent was investigated. The corrosion layer formed on Zn-20Sn-0.5Ag appeared more compact than other alloys. Zinc oxide (ZnO) and Zinc hydroxide (Zn(OH)2) were formed on Zinc alloy surface. Probable mechanisms of Zin...

Key Engineering Materials, 2022

ZTA is considered as one of the most popular ceramic composites that are used for cutting tools d... more ZTA is considered as one of the most popular ceramic composites that are used for cutting tools due to their excellent properties. Consistent efforts should be expanded to achieve improvements in toughness and strength, and thus help them achieve a longer tool life. However, powder compaction process has been found to be a limiting factor in the production of a defect-free ceramic pellet where the green product often ruptures immediately after the compaction process or sintering process. This may be contributed by uneven distribution of pressure load, thus affecting the particles packing and properties of final product. As a solution, the present work aims to study the effect of different compaction pressure on the physical properties of ZTA-TiO2-Cr2O3 ceramic composite to establish a defect-free cutting insert. The samples were fabricated by solid state processing, subjected to pressure loads varied from 200 MPa-350MPa, followed by sintering at 1600°C for 1 hour. The sintered sampl...

Key Engineering Materials, 2022

The purpose of this study is to develop ZTA-MgO-MWCNT cutting insert with enhanced properties and... more The purpose of this study is to develop ZTA-MgO-MWCNT cutting insert with enhanced properties and excellent tool performance that is suitable for high-speed machining. The effects of MWCNT addition on the physical properties of ZTA-MgO composites were investigated. The samples were fabricated using 80:20 composition (80 wt.% of Al2O3: 20 wt.% of YSZ) with fixed amount of MgO at 1.1 wt.% and MWCNT ranging from (0.1 – 0.5 wt.%) as secondary additives. The CNT was pre-treated in ethanol for 1 hour using an ultrasonic homogenizer before mixing and ball milled with Al2O3, YSZ and MgO compositions for 24 hours. The mixture is then pressed at 100 MPa into round-shaped cutting inserts mold after being dried at 100°C for 24 hours. The pressed samples were sintered at 1600 oC for 4 hour soaking time. XRD, density, porosity and shrinkage analysis performed on the samples. The XRD analyses indicate the presence of major phases were α-Al2O3, ZrO2, Zr0.963Y0.037O1.982 and MgAl2O4. The effect of M...

The zirconia toughened alumina enhanced with titania and chromia (ZTA-TiO2-Cr2O3) ceramic cutting... more The zirconia toughened alumina enhanced with titania and chromia (ZTA-TiO2-Cr2O3) ceramic cutting tool is a new cutting tool that possesses good hardness and fracture toughness. However, the performance of the ZTA-TiO2-Cr2O3 cutting tool continues to remain unknown and therefore requires further study. In this research, the wearing of the ZTA-TiO2-Cr2O3 cutting tool and the surface roughness of the machined surface of stainless steel 316L was investigated. The experiments were conducted where the cutting speeds range between 314 to 455 m/min, a feed rate from 0.1 to 0.15 mm/rev, and a depth of cut of 0.2 mm. A CNC lathe machine was utilised to conduct the turning operation for the experiment. Additionally, analysis of the flank wear and crater wear was undertaken using an optical microscope, while the chipping area was observed via scanning electron microscopy (SEM). The surface roughness of the machined surface was measured via portable surface roughness. The lowest value of flank ...

AIP Conference Proceedings, 2019

Hardness and fracture toughness of ZTA samples with addition of SWCNT have been investigated. The... more Hardness and fracture toughness of ZTA samples with addition of SWCNT have been investigated. The composition of Al O /YSZ was constant at 80:20 ratios with the amount of SWCNT varied from 0.00, 0.05, 0.10, 0.30 and 0.50 wt %. The SWCNT was soaked in 20-ml ethanol and dispersed using ultrasonic agitation for 1 hour prior to addition with Al O /YSZ powder using wet mixing. The hardness and fracture toughness were calculated using Vickers indentation techniques. The Vickers hardness results show that presence SWCNT causes agglomeration in the Find more related documents in Scopus based on:

AIP Conference Proceedings, 2019

Zirconia toughened alumina (ZTA) is one of the composite ceramics that are widely use in load bea... more Zirconia toughened alumina (ZTA) is one of the composite ceramics that are widely use in load bearing and wear resistant applications. The composite is known for their good hardness and toughness, due to the presence of both Al O and yttria stabilized zirconia (YSZ). The enhance toughness for ZTA are mostly originated from the presence of YSZ in the composite. The phase transformation from tetragonal to monoclinic that happen inside of YSZ during

IOP Conference Series: Materials Science and Engineering, 2018

Alumina (Al 2 O 3) based ceramics possess good mechanical properties and suitable for the applica... more Alumina (Al 2 O 3) based ceramics possess good mechanical properties and suitable for the application of cutting inserts. However, this monolithic ceramics suffer from lack of toughness. Hence, there are some modification were made such as the addition of yttria stabilized zirconia (YSZ) to the Al 2 O 3 helps in increasing the toughness of the Al 2 O 3 ceramics. Some additives such as MgO and TiO 2 were used to further improve the mechanical properties of ZTA. In this study, high purity raw materials which consist of ZTA-TiO 2 were mixed with different amount of MgO (0.0-1.0 wt %). The mixture of materials was going through wet mixing, compaction and pressureless sintering at 1600 o C for one hour. The samples were characterized for phase analysis, microstructure, shrinkage rate, bulk density, Vickers hardness and fracture toughness. Based on the XRD analysis results, the secondary phase (MgAl 2 O 4) was detected in the sample with 0.5 wt% of MgO onwards which leads to grains refinement, thus improve the density and hardness of ZTA-TiO 2-MgO ceramics composites.

Journal of Alloys and Compounds, 2019

International Journal of Refractory Metals and Hard Materials, 2016

Abstract Increasing demand for stronger cutting tools has led to the development of several novel... more Abstract Increasing demand for stronger cutting tools has led to the development of several novel composites and other multi-phase ceramics with better properties, particularly high fracture toughness. Cr 2 O 3 is used as new material additive in this study, as it has attracted attention due to the formation of isovalent solid solution when added to Al 2 O 3 , contributing to improved fracture toughness. Thus, the aim of this study is to investigate the effects of the addition of Cr 2 O 3 at a concentration of between 0.0 wt% to 1.0 wt% on the physical properties, microstructural features and phase of a ZTA-TiO 2 ceramics composite. The samples were prepared by wet-mixing and uniaxial compaction, then sintered for 1 h at 1600 °C under pressureless conditions. The sintered samples were then identified in terms of their density, hardness, fracture toughness and crack propagation, and were then subjected to microstructural analysis by XRD and FESEM. It was discovered that with addition of 0.6 wt% of Cr 2 O 3 to the composite, an optimum density of 4.0630 g/cm 3 , hardness of 1681 HV, and fracture toughness of 7.15 MPa.m 1/2 were obtained. As a result of this addition, plate-like Al 2 O 3 grains were observed, which caused cracks formed in the composite to spread in an inter-granular manner. This confirmed that the properties of ZTA–TiO 2 ceramics composite were augmented by the addition of 0.6 wt% Cr 2 O 3 .

Materials Science Forum, 2016

Zirconia toughened alumina (ZTA) has good mechanical properties and widely used in cutting insert... more Zirconia toughened alumina (ZTA) has good mechanical properties and widely used in cutting insert application. Although the ZTA is well known of its good mechanical properties, its still can be improved in order to produce better properties. It can be done by adding additives as reinforcement such as magnesium oxide (MgO), cerium oxide (CeO), titania (TiO2) and chromia (Cr2O3). The effect of TiO2-Cr2O3 addition on the physical properties of ZTA were investigated in this study. The composition of TiO2 was varied from 0 wt% to 3.5 wt% while Cr2O3 was fixed at 5 wt%. The starting powder materials were mixed by wet mixing for 30 minutes in acetone. Then the powder mixtures were hydraulically pressed at 260 MPa. The green pellets were sintered at 1600°C for 1 hour using an electrical furnace in presureless condition. The results were characterized by XRD, density, and also Vickers hardness. The ZTA-Cr2O3-TiO2 ceramic composite achieved the highest density of 4.1 g/cm3 and Vickers hardnes...

Materials Science Forum, 2016

ZTA based ceramic composite system is widely accepted as cutting tools for many of these harder a... more ZTA based ceramic composite system is widely accepted as cutting tools for many of these harder and wear resistant workpiece materials. This is due to their beneficial mechanical properties i.e. high temperature strength, high hardness and ability to maintain its cutting edge shape at higher temperatures. Although a lot of works have focused on the effect of various sintering additives on the ZTA ceramic system, the effect of Magnesia (MgO) and Titania (TiO2) on ZTA has not yet been studied. In this work, the physical properties of Zirconia Toughened Alumina (ZTA) ceramic composite with MgO and TiO2 as additives was investigated. The composition of TiO2 varied from 0 wt% to 3.5 wt% whereby other materials such as Al2O3, Yttria Stabilized Zirconia (YSZ) and MgO were kept at constant weight percentage. Sintered samples were then tested and analyzed by XRD, Vickers hardness and high precision densimeter to investigate phase content, hardness value and densification respectively. Result...

Advanced Materials Research, 2015

Ceramic composites consist of zirconia toughened alumina (ZTA) with TiO2as additive was fabricate... more Ceramic composites consist of zirconia toughened alumina (ZTA) with TiO2as additive was fabricated via solid state sintering route. Numerous studies have indicated that TiO2can be used as sintering additives for Al2O3and the ability of microstructural control introduce by TIO2. The Vickers hardness of the obtained ZTA-TiO2was evaluated as a function of different TiO2 addition. Each sample was dry mixed, uniaxially pressed and sintered at 1600 °C for 4 hours in pressureless condition. It is noticed that the presence of TiO2greatly influence the microstructure of Al2O3. Al2O3grains tend to increase in size with more addition of TiO2. Characteristics of Vickers hardness increases increases from 1516.13 HV (0 wt% TiO2) to 1615.8 HV (3 wt% TiO2). Addition of TiO2also increases the bulk density of ZTA-TiO2from 3.90 g/cm3(0 wt% TiO2) to 4.10 g/cm3(3 wt% TiO2).

Ceramics International, 2015

This is a PDF file of an unedited manuscript that has been accepted for publication. As a service... more This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting galley proof before it is published in its final citable form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. www.elsevier.com/locate/ceramint Effects of TiO 2 addition on the phase, mechanical properties, and microstructure of zirconia-toughened alumina ceramic composite Effects of TiO 2 addition on the phase, mechanical properties, and microstructure of zirconia-toughened alumina ceramic composite

Advanced Materials Research, 2012

Stainless steels suffer from classical sensitization when encounter at certain temperature which ... more Stainless steels suffer from classical sensitization when encounter at certain temperature which results in precipitation of chromium carbide along grain boundary with simultaneous depletion of chromium from near grain boundaries. This study focused on corrosion potential test at different sensitization condition. The degree of chromium carbide precipitation was measured based on thickness of grain boundary. With increasing holding time, the thickness of the chromium depletion zone also increases due to diffusion of chromium into solid solution. Corrosion potential test showed that the heated sample at 700°C for 60 minutes resulted in highest corrosion current density and shifted its corrosion potential to more active potential. The potential tend to increase with increasing the degree of chromium carbide precipitation.

IIUM Engineering Journal, 2012

Zinc/MCM-41/air cell, in its dry form without the electrolyte,demonstrates humidity sensing prope... more Zinc/MCM-41/air cell, in its dry form without the electrolyte,demonstrates humidity sensing property. A good linear correlation between the cell's open circuit voltage (OCV) and the relative humidity content is observed. The systempossesses the potential to be developed into a low cost microhumidity sensor. An ultra thin cell of thickness not more than 40 μm has been fabricated and its use as a humiditysensor is substantiated.ABSTRAK: Sel zinc/MCM-41/udara, dalam keadaan kering tanpa elektrolit, menunjukkan sifat pencirian kelembapan. Voltan litar terbuka sel didapati menunjukkan korelasi linear yang baik terhadap kandungan kelembapan relatif. Sistem ini berpotensi untuk dibangunkan menjadi penciri kelembapan mikro yang murah. Sel yang amat nipis dengan ketebalan tidak melebihi 40 μm telah difabrikasi and kegunaannya sebagai penciri kelembapan dibuktikan.

Journal of Advanced Research in Applied Sciences and Engineering Technology

The preference for a ceramic matrix composite, in many applications, is due to its allowance for ... more The preference for a ceramic matrix composite, in many applications, is due to its allowance for alterations, with regards to the filler or reinforcement used. Among the well-known ceramic matrix composites, is the carbon nanotube reinforced ceramic matrix composite. This ceramic composite, which possesses excellent properties, is used exclusively for high-end applications. However, other than the fact that this composite is prone to damage, in a high temperature environment during the sintering process, its use also comes at a high cost. Among the solutions to these drawbacks, is the introduction of carbon into the ceramic composite, through the chemical vapour infiltration (CVI) process. Initially, pyrolysis of biomass is applied on the empty fruit bunch (EFB), for the generation of tar vapour. Pyrolytic carbon is then produced through secondary reaction, during contact with the ceramic surface. The findings, derived from previous studies, indicate that the physical properties of ...

AIP Conference Proceedings

The development of advanced cutting tools for the industrial sectors required materials that can ... more The development of advanced cutting tools for the industrial sectors required materials that can provide a high performance in term of its microstructure, hardness and fracture toughness. Therefore, continuous improvement of ZTA cutting tool is aimed in this research. The purpose of this study is to investigate the effect of single-walled nanotubes (SWNT) addition on physical and microstructural properties of ZTA cutting tools. Ceramic composites with compositions of 80 wt.% of Al2O3 and 20 wt.% YSZ were added with varied amount of SWNT which are 0.05, 0.1, 0.3 and 0.5 wt.%. The SWNT was soaked in 20 mL ethanol under ultrasonic condition for 1 hour and mixed with the composition. These batch of compositions were ball milled for 24 hours before properly dried and powdered. The powder is then pressed into round-shaped cutting inserts mold by the uniaxial pressure of 100 MPa. The prepared samples were sintered at 1600 °C for 4 hours soaking time under pressureless condition. The bulk density and porosity of the sintered sample was identified and SEM images are used to analyze the microstructure of the sample. The effect of SWNT addition was observed on the bulk density, porosity, and microstructure of the sintered samples. The results indicated that the addition of 0.1 wt.% of SWNT to the composite, the highest bulk density of 3.987 g/cm3 was obtained. The small addition of SWNT (< 0.1 wt.%) formed a bridging effect with the Al2O3 and ZrO2 particles. The maximum value of SWNT can be added is 0.1 wt.% where further additions of the SWNT to the composition will reduce the properties of the ZTA cutting tool.The development of advanced cutting tools for the industrial sectors required materials that can provide a high performance in term of its microstructure, hardness and fracture toughness. Therefore, continuous improvement of ZTA cutting tool is aimed in this research. The purpose of this study is to investigate the effect of single-walled nanotubes (SWNT) addition on physical and microstructural properties of ZTA cutting tools. Ceramic composites with compositions of 80 wt.% of Al2O3 and 20 wt.% YSZ were added with varied amount of SWNT which are 0.05, 0.1, 0.3 and 0.5 wt.%. The SWNT was soaked in 20 mL ethanol under ultrasonic condition for 1 hour and mixed with the composition. These batch of compositions were ball milled for 24 hours before properly dried and powdered. The powder is then pressed into round-shaped cutting inserts mold by the uniaxial pressure of 100 MPa. The prepared samples were sintered at 1600 °C for 4 hours soaking time under pressureless condition. The bulk density and porosity of ...

Materials Science Forum, 2020

This paper investigated the performance of ZTA cutting tool with the addition of different partic... more This paper investigated the performance of ZTA cutting tool with the addition of different particle size of MgO additive. Therefore, the objective of this research is to compare the effects of machining parameters on tool wears of ZTA cutting tools added with micro and nanoparticle of MgO. The experiments were conducted using BridgePort-Romi Powerpath CNC machine using a tool holder Sandvik Coromant (CoroTurn CCLNR 164D-4) to hold the cutting tools properly. The parameters are set up as cutting speeds used between range 354 to 472 m/min, feed rate from 0.1 to 0.5 mm/rev with a constant depth of cut of 0.2 mm. Three types of wear were analyzed which are flank wear, crater wear and tool chipping. Flank wear and crater wear images captured using measuring microscope (NIKON MM-400/L) and the crater wear areas are analyzed using MatLab programming software. Tool chipping is observed via SEM (JEOL JSM-5600). The experimental result shows that flank wear and crater wear increase when cutti...

Key Engineering Materials, 2022

This study examines the effect of adding various amount of polyvinyl alcohol (PVA) from 1 wt. % t... more This study examines the effect of adding various amount of polyvinyl alcohol (PVA) from 1 wt. % to 5 wt. % as function to produce porosity of the microstructure on Zirconia-Toughened Alumina (ZTA). Porosity is required in this study which aims to increase the efficiency of carbon infiltration on the porous composite through chemical vapor infiltration (CVI). Moreover, carbon production from empty fruit bunch (EFB) was used as a reinforcement on ceramic composites in this system. The microstructure of samples was characterised by using scanning electron microscopy (SEM). The density shows the lowest at 2.864 g/cm3 when the percentage of binder is increased at 4wt.% of PVA without carbon infiltration but shows the highest density value which is 4.107 g/cm3 after carbon is infiltrated. Vickers hardness was used to identify the hardness of samples. It was found that ZTA composite with infiltrated carbon has better hardness (2053HV) with addition of 4wt.% of PVA. However, firing shrinkag...

Key Engineering Materials, 2022

The ZTA-TiO2-Cr2O3 ceramic cutting tool is a new cutting tool that possesses good hardness and fr... more The ZTA-TiO2-Cr2O3 ceramic cutting tool is a new cutting tool that possesses good hardness and fracture toughness. Yet, the performance of the ZTA-TiO2-Cr2O3 cutting tool is still unknown and needs further study. In this research, the comparison of the ZTA-TiO2-Cr2O3 and Kennametal ceramic cutting tool is investigated. The turning process by using ZTA-TiO2-Cr2O3 and Kennametal commercial ceramic cutting tools is performed on the Bridgeport ROMI PowerPath CNC lathe machine. The parameters utilized are spindle speed in the range of 907 to 1543 rpm, feed rate from 0.08 to 0.22 mm/rev, and depth of cut of 0.2 mm. Analysis of the flank wear and crater wear were performed by using an optical microscope (NIKON MM-4001L), while the chipping area was observed by scanning electron microscopy, SEM (JEOL JSM-IT100). The surface roughness of the machined surface is measured via portable surface roughness (Mahr MarSurf M3000C). The comparison between the cutting tool produced in this research and...

Journal of Engineering and Science Research, 2021

The electrochemical and corrosion behaviour of Zn-20Sn and Zn-0.50Ag alloys in dishwasher deterge... more The electrochemical and corrosion behaviour of Zn-20Sn and Zn-0.50Ag alloys in dishwasher detergent solution was investigated by Tafel plot and characterized X-ray diffraction (XRD) and Scanning Electrode Microscope (SEM). The measurements were conducted using different composition of elements addition (Ag: 0.03%, 0.27% and 0.50%. Sn: 1%, 8%, and 15%) under the same experimental conditions. The results showed that the addition of Ag led to decreased corrosion rate compared to Sn addition. The corrosion potential for Zn alloy with Ag addition are shifted towards more noble values compared to Zn alloys with Sn addition . By adding Ag, the current density is decreased and thus reducing the hydrogen evolution rate. The corrosion layer formed on Zinc sample in dishwasher detergent was investigated. The corrosion layer formed on Zn-20Sn-0.5Ag appeared more compact than other alloys. Zinc oxide (ZnO) and Zinc hydroxide (Zn(OH)2) were formed on Zinc alloy surface. Probable mechanisms of Zin...

Key Engineering Materials, 2022

ZTA is considered as one of the most popular ceramic composites that are used for cutting tools d... more ZTA is considered as one of the most popular ceramic composites that are used for cutting tools due to their excellent properties. Consistent efforts should be expanded to achieve improvements in toughness and strength, and thus help them achieve a longer tool life. However, powder compaction process has been found to be a limiting factor in the production of a defect-free ceramic pellet where the green product often ruptures immediately after the compaction process or sintering process. This may be contributed by uneven distribution of pressure load, thus affecting the particles packing and properties of final product. As a solution, the present work aims to study the effect of different compaction pressure on the physical properties of ZTA-TiO2-Cr2O3 ceramic composite to establish a defect-free cutting insert. The samples were fabricated by solid state processing, subjected to pressure loads varied from 200 MPa-350MPa, followed by sintering at 1600°C for 1 hour. The sintered sampl...

Key Engineering Materials, 2022

The purpose of this study is to develop ZTA-MgO-MWCNT cutting insert with enhanced properties and... more The purpose of this study is to develop ZTA-MgO-MWCNT cutting insert with enhanced properties and excellent tool performance that is suitable for high-speed machining. The effects of MWCNT addition on the physical properties of ZTA-MgO composites were investigated. The samples were fabricated using 80:20 composition (80 wt.% of Al2O3: 20 wt.% of YSZ) with fixed amount of MgO at 1.1 wt.% and MWCNT ranging from (0.1 – 0.5 wt.%) as secondary additives. The CNT was pre-treated in ethanol for 1 hour using an ultrasonic homogenizer before mixing and ball milled with Al2O3, YSZ and MgO compositions for 24 hours. The mixture is then pressed at 100 MPa into round-shaped cutting inserts mold after being dried at 100°C for 24 hours. The pressed samples were sintered at 1600 oC for 4 hour soaking time. XRD, density, porosity and shrinkage analysis performed on the samples. The XRD analyses indicate the presence of major phases were α-Al2O3, ZrO2, Zr0.963Y0.037O1.982 and MgAl2O4. The effect of M...

The zirconia toughened alumina enhanced with titania and chromia (ZTA-TiO2-Cr2O3) ceramic cutting... more The zirconia toughened alumina enhanced with titania and chromia (ZTA-TiO2-Cr2O3) ceramic cutting tool is a new cutting tool that possesses good hardness and fracture toughness. However, the performance of the ZTA-TiO2-Cr2O3 cutting tool continues to remain unknown and therefore requires further study. In this research, the wearing of the ZTA-TiO2-Cr2O3 cutting tool and the surface roughness of the machined surface of stainless steel 316L was investigated. The experiments were conducted where the cutting speeds range between 314 to 455 m/min, a feed rate from 0.1 to 0.15 mm/rev, and a depth of cut of 0.2 mm. A CNC lathe machine was utilised to conduct the turning operation for the experiment. Additionally, analysis of the flank wear and crater wear was undertaken using an optical microscope, while the chipping area was observed via scanning electron microscopy (SEM). The surface roughness of the machined surface was measured via portable surface roughness. The lowest value of flank ...

AIP Conference Proceedings, 2019

Hardness and fracture toughness of ZTA samples with addition of SWCNT have been investigated. The... more Hardness and fracture toughness of ZTA samples with addition of SWCNT have been investigated. The composition of Al O /YSZ was constant at 80:20 ratios with the amount of SWCNT varied from 0.00, 0.05, 0.10, 0.30 and 0.50 wt %. The SWCNT was soaked in 20-ml ethanol and dispersed using ultrasonic agitation for 1 hour prior to addition with Al O /YSZ powder using wet mixing. The hardness and fracture toughness were calculated using Vickers indentation techniques. The Vickers hardness results show that presence SWCNT causes agglomeration in the Find more related documents in Scopus based on:

AIP Conference Proceedings, 2019

Zirconia toughened alumina (ZTA) is one of the composite ceramics that are widely use in load bea... more Zirconia toughened alumina (ZTA) is one of the composite ceramics that are widely use in load bearing and wear resistant applications. The composite is known for their good hardness and toughness, due to the presence of both Al O and yttria stabilized zirconia (YSZ). The enhance toughness for ZTA are mostly originated from the presence of YSZ in the composite. The phase transformation from tetragonal to monoclinic that happen inside of YSZ during

IOP Conference Series: Materials Science and Engineering, 2018

Alumina (Al 2 O 3) based ceramics possess good mechanical properties and suitable for the applica... more Alumina (Al 2 O 3) based ceramics possess good mechanical properties and suitable for the application of cutting inserts. However, this monolithic ceramics suffer from lack of toughness. Hence, there are some modification were made such as the addition of yttria stabilized zirconia (YSZ) to the Al 2 O 3 helps in increasing the toughness of the Al 2 O 3 ceramics. Some additives such as MgO and TiO 2 were used to further improve the mechanical properties of ZTA. In this study, high purity raw materials which consist of ZTA-TiO 2 were mixed with different amount of MgO (0.0-1.0 wt %). The mixture of materials was going through wet mixing, compaction and pressureless sintering at 1600 o C for one hour. The samples were characterized for phase analysis, microstructure, shrinkage rate, bulk density, Vickers hardness and fracture toughness. Based on the XRD analysis results, the secondary phase (MgAl 2 O 4) was detected in the sample with 0.5 wt% of MgO onwards which leads to grains refinement, thus improve the density and hardness of ZTA-TiO 2-MgO ceramics composites.

Journal of Alloys and Compounds, 2019

International Journal of Refractory Metals and Hard Materials, 2016

Abstract Increasing demand for stronger cutting tools has led to the development of several novel... more Abstract Increasing demand for stronger cutting tools has led to the development of several novel composites and other multi-phase ceramics with better properties, particularly high fracture toughness. Cr 2 O 3 is used as new material additive in this study, as it has attracted attention due to the formation of isovalent solid solution when added to Al 2 O 3 , contributing to improved fracture toughness. Thus, the aim of this study is to investigate the effects of the addition of Cr 2 O 3 at a concentration of between 0.0 wt% to 1.0 wt% on the physical properties, microstructural features and phase of a ZTA-TiO 2 ceramics composite. The samples were prepared by wet-mixing and uniaxial compaction, then sintered for 1 h at 1600 °C under pressureless conditions. The sintered samples were then identified in terms of their density, hardness, fracture toughness and crack propagation, and were then subjected to microstructural analysis by XRD and FESEM. It was discovered that with addition of 0.6 wt% of Cr 2 O 3 to the composite, an optimum density of 4.0630 g/cm 3 , hardness of 1681 HV, and fracture toughness of 7.15 MPa.m 1/2 were obtained. As a result of this addition, plate-like Al 2 O 3 grains were observed, which caused cracks formed in the composite to spread in an inter-granular manner. This confirmed that the properties of ZTA–TiO 2 ceramics composite were augmented by the addition of 0.6 wt% Cr 2 O 3 .

Materials Science Forum, 2016

Zirconia toughened alumina (ZTA) has good mechanical properties and widely used in cutting insert... more Zirconia toughened alumina (ZTA) has good mechanical properties and widely used in cutting insert application. Although the ZTA is well known of its good mechanical properties, its still can be improved in order to produce better properties. It can be done by adding additives as reinforcement such as magnesium oxide (MgO), cerium oxide (CeO), titania (TiO2) and chromia (Cr2O3). The effect of TiO2-Cr2O3 addition on the physical properties of ZTA were investigated in this study. The composition of TiO2 was varied from 0 wt% to 3.5 wt% while Cr2O3 was fixed at 5 wt%. The starting powder materials were mixed by wet mixing for 30 minutes in acetone. Then the powder mixtures were hydraulically pressed at 260 MPa. The green pellets were sintered at 1600°C for 1 hour using an electrical furnace in presureless condition. The results were characterized by XRD, density, and also Vickers hardness. The ZTA-Cr2O3-TiO2 ceramic composite achieved the highest density of 4.1 g/cm3 and Vickers hardnes...

Materials Science Forum, 2016

ZTA based ceramic composite system is widely accepted as cutting tools for many of these harder a... more ZTA based ceramic composite system is widely accepted as cutting tools for many of these harder and wear resistant workpiece materials. This is due to their beneficial mechanical properties i.e. high temperature strength, high hardness and ability to maintain its cutting edge shape at higher temperatures. Although a lot of works have focused on the effect of various sintering additives on the ZTA ceramic system, the effect of Magnesia (MgO) and Titania (TiO2) on ZTA has not yet been studied. In this work, the physical properties of Zirconia Toughened Alumina (ZTA) ceramic composite with MgO and TiO2 as additives was investigated. The composition of TiO2 varied from 0 wt% to 3.5 wt% whereby other materials such as Al2O3, Yttria Stabilized Zirconia (YSZ) and MgO were kept at constant weight percentage. Sintered samples were then tested and analyzed by XRD, Vickers hardness and high precision densimeter to investigate phase content, hardness value and densification respectively. Result...

Advanced Materials Research, 2015

Ceramic composites consist of zirconia toughened alumina (ZTA) with TiO2as additive was fabricate... more Ceramic composites consist of zirconia toughened alumina (ZTA) with TiO2as additive was fabricated via solid state sintering route. Numerous studies have indicated that TiO2can be used as sintering additives for Al2O3and the ability of microstructural control introduce by TIO2. The Vickers hardness of the obtained ZTA-TiO2was evaluated as a function of different TiO2 addition. Each sample was dry mixed, uniaxially pressed and sintered at 1600 °C for 4 hours in pressureless condition. It is noticed that the presence of TiO2greatly influence the microstructure of Al2O3. Al2O3grains tend to increase in size with more addition of TiO2. Characteristics of Vickers hardness increases increases from 1516.13 HV (0 wt% TiO2) to 1615.8 HV (3 wt% TiO2). Addition of TiO2also increases the bulk density of ZTA-TiO2from 3.90 g/cm3(0 wt% TiO2) to 4.10 g/cm3(3 wt% TiO2).

Ceramics International, 2015

This is a PDF file of an unedited manuscript that has been accepted for publication. As a service... more This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting galley proof before it is published in its final citable form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. www.elsevier.com/locate/ceramint Effects of TiO 2 addition on the phase, mechanical properties, and microstructure of zirconia-toughened alumina ceramic composite Effects of TiO 2 addition on the phase, mechanical properties, and microstructure of zirconia-toughened alumina ceramic composite

Advanced Materials Research, 2012

Stainless steels suffer from classical sensitization when encounter at certain temperature which ... more Stainless steels suffer from classical sensitization when encounter at certain temperature which results in precipitation of chromium carbide along grain boundary with simultaneous depletion of chromium from near grain boundaries. This study focused on corrosion potential test at different sensitization condition. The degree of chromium carbide precipitation was measured based on thickness of grain boundary. With increasing holding time, the thickness of the chromium depletion zone also increases due to diffusion of chromium into solid solution. Corrosion potential test showed that the heated sample at 700°C for 60 minutes resulted in highest corrosion current density and shifted its corrosion potential to more active potential. The potential tend to increase with increasing the degree of chromium carbide precipitation.

IIUM Engineering Journal, 2012

Zinc/MCM-41/air cell, in its dry form without the electrolyte,demonstrates humidity sensing prope... more Zinc/MCM-41/air cell, in its dry form without the electrolyte,demonstrates humidity sensing property. A good linear correlation between the cell's open circuit voltage (OCV) and the relative humidity content is observed. The systempossesses the potential to be developed into a low cost microhumidity sensor. An ultra thin cell of thickness not more than 40 μm has been fabricated and its use as a humiditysensor is substantiated.ABSTRAK: Sel zinc/MCM-41/udara, dalam keadaan kering tanpa elektrolit, menunjukkan sifat pencirian kelembapan. Voltan litar terbuka sel didapati menunjukkan korelasi linear yang baik terhadap kandungan kelembapan relatif. Sistem ini berpotensi untuk dibangunkan menjadi penciri kelembapan mikro yang murah. Sel yang amat nipis dengan ketebalan tidak melebihi 40 μm telah difabrikasi and kegunaannya sebagai penciri kelembapan dibuktikan.