Structure and mechanical properties of Ni/Ti multilayered composites produced by accumulative roll-bonding process (original) (raw)
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Materials Science Engineering a Structural Materials Properties Microstructure and Processing, 2007
The effects of Ni foil thickness on the microstructure and tensile properties of reaction synthesized multilayer composites have been systematically investigated. Multilayer composites have been fabricated by reaction annealing of their foil laminates consisting of 10 m thick Al foils and 20, 50 and 80 m thick Ni foils. Ni 3 Al multilayer composites prepared from 20 m Ni foils were very brittle. Ni/Ni 3 Al multilayer composites prepared from 50 m Ni foils exhibited significant work-hardening and behaved more like a ductile alloy, rather than a composite, with an ultimate tensile strength of 1050 MPa and elongations of >18%. The composites fabricated from 80 m Ni foils, which contain Ni 3 Al precipitates, had a low yield strength and ultimate tensile strength (about 160 and 470 MPa, respectively), and had a very good capacity for plastic deformation (>34% elongation). The dislocations in Ni and Ni 3 Al layers can slide through the Ni 3 Al/Ni interfaces, with the result that the Ni and the Ni 3 Al layers in the composites can cooperatively deform during tensile testing. Delaminated interfaces containing Al 2 O 3 inclusions further promote the capability of the Ni 3 Al layers for plastic deformation. As a result, the Ni/Ni 3 Al multilayer composites exhibit good tensile strengths and a high ductility. The existence of Ni 3 Al precipitates in the Ni layers inhibits cross-slip of dislocations, which results in dislocation networks in the Ni layers which have a preferred orientation.
Journal of Materials Engineering and Performance, 2012
The present investigation is an attempt to develop metal-intermetallic laminate composites based on Ni-Al system. In this study, Ni sheets and Al foils have been used for the development of Ni-Al laminate using accumulative roll-bonding technique at 773 K. The laminate composites were then subjected to the controlled annealing to affect reactive diffusion at the Ni/Al interface leading to intermetallic compound formation. The accumulative roll-bonded laminates showed good bonding of layers. Annealing treatment at 773 K led to formation of reaction product and maintained the interface integrity. A qualitative compositional analysis at the interfaces reflected the formation of Al-Ni compounds, and a gradual compositional gradient also across the interface. This process seems to be of promise so far as the continuous production of large scale metal-intermetallic laminate composites is concerned.
Ni/Ti and Ni/Al Laminated Composites Produced by ARB and Annealing: Microstructural Aspects
Microscopy and microanalysis : the official journal of Microscopy Society of America, Microbeam Analysis Society, Microscopical Society of Canada, 2015
Accumulative roll bonding (ARB) is a combination of forming and bonding processes. So, this is a high promising technique to produce bulk solid materials composed of more than one constituent. ARB has been applied to strengthen metals and to produce laminated metal-metal or nonmetal-metal composites, e.g. intermetallic composites, shape memory alloys or reactive foils [1, 2]. Since ARB is performed at room temperature, the formation of new phases can be avoided. This technique is also capable of mass production and it can fabricate thick foils, using simple and cheap equipment. This essay compares two bimodal multilayer foils: Ni/Ti and Ni/Al. Input materials include foils of 99.98 wt% Ni-125 µm thick, 99.00 wt% Al-200 µm thick and 99.6 wt% Ti-200 µm thick. Rolling was done with a strain rate of 20 s-1 at room temperature. Rolled batches after 4 and 10 cycles were characterized by optical and scanning electron microscopies. Energy dispersive spectroscopy (EDS) as chemical analysis technique was used to identify phases evolved in the multilayers during processing. Electron backscattering diffraction (EBSD) technique also assisted phase identification.
Al/Ni metal intermetallic composite produced by accumulative roll bonding and reaction annealing
Journal of Alloys and Compounds, 2011
In this research, Al/Ni multilayers composites were produced by accumulative roll bonding and then annealed at different temperatures and durations. The structure and mechanical properties of the fabricated metal intermetallic composites (MICs) were investigated. Scanning electron microscopy and X-ray diffraction analyses were used to evaluate the structure and composition of the composite. The Al 3 Ni intermetallic phase is formed in the Al/Ni interface of the samples annealed at 300 and 400 • C. When the temperature increased to 500 • C, the Al 3 Ni 2 phase was formed in the composite structure and grew, while the Al 3 Ni and Al phases were simultaneously dissociated. At these conditions, the strength of MIC reached the highest content and was enhanced by increasing time. At 600 • C, the AlNi phase was formed and the mechanical properties of MIC were intensively degraded due to the formation of structural porosities.
Materials Science and Engineering: A, 2012
Al-Ni-Cu composite was produced using accumulative roll bonding (ARB) and electroplating processes. Nickel was electroplated on copper substrate for a certain time and voltage. In this study, the microstructural evolution and mechanical properties of the Al-Ni-Cu composite during various ARB cycles were studied by optical and scanning electron microscopes, microhardness, tensile and bending tests. It was observed that at first, nickel layers and then copper layers, were necked, fractured and distributed in aluminum matrix as accumulative roll bonding cycles were increased. Finally, after 11 cycles of ARB process, a completely uniform composite was produced with a homogeneous distribution of copper and nickel particles in aluminum matrix. The results showed that by increasing the number of ARB cycles, the bending strength of produced composite was increased. Also, it was found that when the number of cycles was increased, not only elongation was increased but also the tensile strength of the composite was improved. Microhardness for different elements in different cycles was also evaluated. Finally, fracture surfaces of samples were studied, using scanning electron microscopy (SEM), to reveal the failure mechanism.
Microstructure, Texture, and Mechanical Properties of Ni-W Alloy After Accumulative Roll Bonding
Journal of Materials Engineering and Performance, 2018
In this study, the microstructure, texture, and mechanical properties evolution of Ni-14W (wt. %) alloy processed up to four cycles of accumulative roll-bonding (ARB) were investigated using electron backscatter diffraction, microhardness measurements, and tensile tests. The initial equiaxed grains, with an average size of 10 μm, underwent a strong refinement after ARB processing. The elongated ultrafine grains were parallel to the rolling direction, with a grain thickness of 0.2 µm. The texture after ARB processing was characterized by the typical rolling components (Copper, S and Brass), which showed a tendency toward stabilization after four cycles. The microhardness increased substantially (+86%) and seemed to saturate after three cycles. The tensile tests demonstrated that Ni-14W samples subjected to ARB processing exhibited high strength (> 1200 MPa after three ARB cycles) and very poor ductility.
Metals, 2019
In this work, the interface characteristics and resulting bond strength were investigated for roll bonded steel-aluminum composites with nickel interlayers, both after rolling and after post-rolling heat treatments at 400 °C–550 °C. After rolling, only mechanical interlocking was achieved between the steel and nickel layers, which resulted in delamination. Post-rolling heat treatments resulted in sufficient metallurgical bonding between the steel and nickel layers, and a significant increase in the bond strength. An intermetallic phase layer formed during the heat treatments, which below 500 °C consisted of Al3Ni and above, Al3Ni and Al3Ni2. With increasing temperature and time, the Al3Ni2 phase consumed the Al3Ni layer, voids developed along the Al3Ni2-aluminum interface, and a duplex morphology developed inside the Al3Ni2 layer, in accordance with the Kirkendall effect. The highest bond strength was obtained for the composites that only had an Al3Ni layer along the interface, and ...
Cold rolled versus sputtered Ni/Ti multilayers for reaction-assisted diffusion bonding
Welding in the World, 2015
Reaction-assisted diffusion bonding of TiNi to Ti6Al4V was carried out using two types of filler materials: (i) Ni/Ti multilayer foils produced by accumulative roll bonding (ARB) and (ii) Ni/Ti multilayer thin films prepared by magnetron sputtering. In ARB, nanostructures were produced through severe plastic deformation by stacking alternated Ni and Ti foils and rolling at a strain rate of 20 s −1 up to 16 cycles, attaining a total thickness close to 300 μm. Using ARB Ni/Ti ultrafine multilayers, it was possible to achieve sound joints at undemanding conditions for a solid-state joining process (800°C/10 MPa/60 min), with a shear strength of 35 MPa. The layered structure of the foil transforms into TiNi with small regions of Ti 2 Ni and TiNi 3 ; a continuous layer of Ti 2 Ni is observed close to the Ti6Al4V base material. Ni/Ti multilayer thin films with nanometric modulation periods have also been successfully used to produce sound joints at 750 and 800°C, under 10 or 50 MPa during 60 min, with a shear strength of 88 MPa. The interface is very thin (less than 10 μm) and exhibits several zones; comprising a Ti 2 Ni layer close to the Ti6Al4V alloy, followed by TiNi and Ti 2 Ni phases.
This article discusses the correlation between the microstructural and mechanical changes in the dual-matrix Al-Ni/SiC composites processed by Accumulative Roll Bonding (ARB) technique. Three different SiC concentrations, 1, 3, and 5% were considered to reinforce Al and Al-Ni dual-matrix composites. ARB process was applied up to 7 cycles to manufacture a composite with homogenous dispersion of the three phases. The results showed that the presence of Ni layer between Al and SiC particles enhanced the dispersion of SiC in the matrix, which positively affect the mechanical strength. The maximum tensile achieved was 257 MPa for composite containing 3 % SiC after 7 ARB cycles compared to 37.2 MPa for the AA1050. Increasing SiC content reduces the adhesion between Al and Ni layers, which reduces the elasticity of the composites. However, for the composites with 5% SiC, after 3 ARB cycles, the strength was reduced due to the cracking of the Ni layer caused by the stress concentration around the SiC particles. The hardness values of the ARBed AA1050, AA1050-Ni, and AA1050-Ni/5 wt% SiC are 85.5, 93.5, and 109.7, respectively, after 7 ARB cycles. In terms of strength, the samples with 3% SiC content showed the optimum stress enhancement with minimum reduction in the elongation, which achieve a compromised response for many applications.