Annamaria Gisario - Academia.edu (original) (raw)

Papers by Annamaria Gisario

Optics and Lasers in Engineering, 2010

Heat treatment of ceramic-reinforced aluminium matrix composites (AMCs) using a high-power diode ... more Heat treatment of ceramic-reinforced aluminium matrix composites (AMCs) using a high-power diode laser (HPDL) was investigated. AMCs were treated by irradiation with laser beams of different power and scanning speeds. This resulted in significant changes in the overall appearance and microstructure of the composite material. Contact gauge profilometry and combined SEM-EDXS and XRD analyses were performed to investigate the relationship between changes in the morphology and microstructure to the amount of laser energy delivered. Vickers microhardness and tribological tests were performed to identify changes in the local mechanical properties of the composite material. Laser treatment often improves the properties of AMCs, although setting of the operational parameters is crucial. In fact, small deviations in power and/or scan speed can severely damage the material, leading to deterioration of the microstructure and overall mechanical behaviour.

Surface and Coatings Technology, Aug 1, 2006

A neural network approach is used to model a paint stripping process performed using a 1.5 kW con... more A neural network approach is used to model a paint stripping process performed using a 1.5 kW continuous diode laser source on an aluminum substrate coated with approximately 80 μm of a hybrid epoxy-polyester resin. Two different coating colors, namely RAL 8087 (dark) and RAL 1013 (bright), are examined in order to analyze the influence of the difference in absorption of the laser energy by the surface on process.

Progress in Organic Coatings, Dec 1, 2006

This paper deals with the analysis of the evolution of the surface morphology of metal substrates... more This paper deals with the analysis of the evolution of the surface morphology of metal substrates coated with high-performance thermoplastic powders, namely PPA 571 H, by using electrostatic fluidized bed (EFB) process. Attention has been particularly focused on the relationship between baking time and temperature of EFB coated substrates and the morphological characteristics of the resulting polymeric films.

International Journal of Refractory Metals and Hard Materials, 2015

ABSTRACT The present work deals with the post-treatment of thermally-sprayed WC–Co/NiCr coatings ... more ABSTRACT The present work deals with the post-treatment of thermally-sprayed WC–Co/NiCr coatings deposited by (High Velocity Oxygen Fuel) HVOF on a cylindrical substrate in AA 6082 T6 aluminium alloy with a High Power Diode Laser (HPDL). Laser operational parameters, especially laser power and scan rate, were investigated to find the best settings to improve the mechanical response of the WC–Co/NiCr coatings, preventing the onset of surface damage. Visual appearance and morphology of the coatings were investigated by contact gauge profilometry and scanning electron microscopy. The material microstructure was studied by combined scanning electron microscopy and energy dispersive X-ray spectroscopy. Hardness and wear resistance were analysed by instrumented indentation tests. Appropriate combinations of laser parameters were found to enhance significantly the mechanical performance of the WC–Co/NiCr coatings, whose structure was dense, compact and uniform, with hardness and wear endurance highly improved. In contrast, extreme irradiation densities of the laser beam should be carefully avoided to reduce the onset of defectiveness as wide fractures and/or additional porosities inside the thermally sprayed material.

Journal of Coatings Technology and Research, 2014

In the present investigation, scratch resistance, chemical inertness and corrosion resistance of ... more In the present investigation, scratch resistance, chemical inertness and corrosion resistance of methyl phenyl polysiloxane coatings on Fe 430 B structural steel with or without an organo-silane intermediate layer were analyzed. The role of Al-Mg pigments dispersed in the resin was studied, too. The high molecular weight of the polysiloxane resin ensures good adhesion to the substrate, low porosity and high mechanical stability. The good ductility and low steric hindrance of the methyl groups coupled with the chemical inertness of the phenyl groups yields coatings with utmost endurance to aggressive chemicals and, above all, suitable as corrosion retardants on sensitive steel substrates. Lastly, the dispersion in the resin of particles, which act as corrosion inhibitor, as well as the interposition of organo-silane layers between substrate and polysiloxane resin can improve further the potentiality of the designed barrier coatings.

Engineering Science and Technology, an International Journal, 2014

Drag finishing of brass (Cu-30 wt.% Zn) rings using fluidized abrasives, which is a new finishing... more Drag finishing of brass (Cu-30 wt.% Zn) rings using fluidized abrasives, which is a new finishing technology, is comparatively evaluated with centrifugal disk finishing. The comparison was performed by selecting the same abrasive granulates of two different sizes and operating the equipment for the same processing time or at their respective maximum speeds. The experimental analysis investigated the change in workpiece morphology, material removal during finishing and dimensional accuracy. The results showed that each of the types of equipment investigated in the study were capable of a high finishing performance with a relatively short processing time. However, fluidized bed assisted drag finishing was more effective than centrifugal disk finishing in both the achievable quality of the processed parts and reduced processing time. In contrast, centrifugal disk finishing was preferable whenever low erosion and stringent dimensional tolerances were demanded.

Wear, 2011

A novel method using a high power diode laser to selectively remove cobalt binder from the outerm... more A novel method using a high power diode laser to selectively remove cobalt binder from the outermost layer of Co-cemented tungsten carbide (WC-Co 5.8 wt.%) is hereby discussed. A continuous 940-nm wavelength diode laser source at power of 600-1500 W and scanning speed of 1 mm/s was used to perform the thermal treatments. Hot Filament-Chemical Vapour Deposition (HF-CVD) was then used to deposit PolyCrystalline Diamond (PCD) coatings. Increasing the laser fluence, Co-binder was progressively and selectively evaporated from the WC-Co substrate. The selective removal of the Co-binder from the outermost layer of WC-Co induces a significant corrugation of the substrate, very promising to deposit on it high quality diamond with improved adhesion. Indeed, too much high laser fluence must be avoided, as it would tend to induce the resintering or the local melting of the tungsten carbide grains.

Manufacturing Letters, 2013

Abrasive Fluidized Bed (AFB) finishing of cobalt-chromium coatings is investigated. Cylindrical m... more Abrasive Fluidized Bed (AFB) finishing of cobalt-chromium coatings is investigated. Cylindrical metal components coated by High Velocity Oxygen Fuel (HVOF) with Stellite 6 were machined, while rotating at high speed in a bed of suspended Al 2 O 3 abrasives. The interaction between abrasives and coatings was analyzed varying the machining time, abrasive size and rotational speed. The morphology and dimensional stability of the machined parts was monitored by microscopy, profilometry and dimensional analysis. AFB is able to smoothen the morphology of the Stellite 6 coatings, preserving their dimensional accuracy. This makes AFB a promising technique in the reprocessing of hard coatings.

International Journal of Material Forming, 2010

In this paper, morphological and thermal effects induced on sintered bronze substrates by diode l... more In this paper, morphological and thermal effects induced on sintered bronze substrates by diode laser polishing are investigated. The influence of laser power and interaction time was looked into. The evolution of surface morphology was evaluated by scanning electron microscopy and contact-gauge profilometry. Maximum depth of the groove generated by laser on the material was related to amplitude, spacing and hybrid roughness parameters. Experimental results show a decrease in roughness of ~ 50% is reachable if out of tolerance of ~ 200 μm is acceptable. Particular efforts were dedicated to understand the mechanisms involved during the laser treatment and the way by which the final surface morphology was established. In this respect, a thermographic analysis was performed on treated sample to evaluate variations in thermal effusivity. Accordingly, a preliminary experimental model was proposed to approximate the real operational conditions and predict the most promising settings of the laser system aimed at improving the surface finishing of the metal substrates.

Tribology International, 2013

The development of effective coating systems that offer high protection against erosioncorrosion ... more The development of effective coating systems that offer high protection against erosioncorrosion is of utmost importance in several industrial sectors. Such a coating class is typically designed to provide an effective barrier against aggressive environments combined with cathodic protection. The adherence to the substrate ensures full performance and reliability of the coatings during service. In the present investigation, the scratch response of single-and multi-layered composite coatings made from superimposed layers of a modified phenyl-methyl silicone resin and of aluminum-magnesium (Al-Mg 4.5 wt.%) metallic powders was investigated. The applied loads, the contact conditions between the indenter and coating surface and the sliding speeds were analyzed, and empirical models were developed accordingly. The scratch response of the composite coatings was mapped according to the testing conditions, thus providing a useful instrument for designers and practitioners.

Surface and Coatings Technology, 2006

This paper deals with a primerless electrostatic spray deposition process (ESD) for coating therm... more This paper deals with a primerless electrostatic spray deposition process (ESD) for coating thermoplastic (PA66) substrates using epoxypolyester, metallic epoxy-polyester, and epoxy powder paint. A novel and never before used pretreatment system, based on a low speed cold spray of fine copper powders, applied a thin conductive film on the plastic substrate, which made the ESD possible.

Surface and Coatings Technology, 2006

This paper deals with an electrostatic spray deposition (ESD) process of 'self organizing' TiO 2 ... more This paper deals with an electrostatic spray deposition (ESD) process of 'self organizing' TiO 2 -epoxy powder paints on metal substrates. The first part of the paper focuses on analyzing the influence of both electrical and aerodynamic operational parameters on ESD process. Design of experiments (DOE) was used to plan experimental trials. ANOVA tables were calculated and used as support instruments to interpret the experimental findings and to understand physical phenomena involved in the deposition process as well as the role of TiO 2 . As a result, several process maps were produced which report consistent trends in coating thickness versus operational parameters. Best deposition conditions could therefore be deduced. Initial attempts to produce 'self-organizing' TiO 2 -based gradient coatings are also discussed.

Surface and Coatings Technology, 2006

A neural network approach is used to model a paint stripping process performed using a 1.5 kW con... more A neural network approach is used to model a paint stripping process performed using a 1.5 kW continuous diode laser source on an aluminum substrate coated with approximately 80 μm of a hybrid epoxy-polyester resin. Two different coating colors, namely RAL 8087 (dark) and RAL 1013 (bright), are examined in order to analyze the influence of the difference in absorption of the laser energy by the surface on process.

Surface and Coatings Technology, 2008

This paper deals with the development and application of a new technique, Fast Regime-Fluidized B... more This paper deals with the development and application of a new technique, Fast Regime-Fluidized Bed Machining (FR-FBM), for the easy-to-automate finishing of as-deposited Atmospheric Plasma Spraying (APS) TiO 2 coatings on AISI 1040 steel substrates. The effects of leading FBM ...

Surface and Coatings Technology, 2011

The scratch performance of powder-coated substrates depends on many factors, including the coatin... more The scratch performance of powder-coated substrates depends on many factors, including the coating material and thickness, the deposition techniques, and the characteristics of the baking processes. In the present investigation, two thermoplastic (PPA571, an alloy of acid-modified polyolefins) and thermoset (TGIC-free, transparent, bronze-pigmented polyester) organic powders were deposited onto flat aluminium substrates by the 'hot dipping' fluidised bed and electrostatic spray coating technologies. In the former technology, the metal substrates were pre-heated to 300°C before being dipped in the fluidised bed and powder coated. In the latter technology, after electrostatic painting, the coated substrates were submitted to a curing process for 20 min at 170°C to allow the formation of continuous films. The resulting coatings differed in morphology, thickness and adhesion strength. The scratch responses of the coatings were evaluated by progressive-mode scratch tests. Different contact conditions between the scratching geometry and the coating surface were analysed using three conical (Rockwell C) diamond indenters with tip radii of 100, 200 and 800 m. Electrostatically sprayed thermoset coatings showed a better overall scratch resistance with minor deformation events and damage of a lesser extent compared to the thermoplastic coatings. On the contrary, the thermoplastic coatings displayed very singular scratch properties regardless of the deposition process, having the largest deformation events and most massive interfacial rupture.

Progress in Organic Coatings, 2009

The knowledge of the properties of the coatings in terms of scratch and wear resistance is of par... more The knowledge of the properties of the coatings in terms of scratch and wear resistance is of paramount importance in order to prevent the formation of severe damages. Nonetheless, dealing with the evaluation scratch or wear resistance of an organic coating can be troublesome. They can be strongly dependent on the status of the organic material as well as on the contact condition, applied load and strain rate. Besides, reliable responses cannot be achieved if an appropriate experimental design and a combined usage of proper equipments is not scheduled. In this respect, the present analysis deals with the application of variable speed and load scratch tests to characterize the scratch response and wear resistance of bilayer metal flakes powder coatings. Experimental findings allowed the achievement of consistent trends of the deformation response vs. curing temperature, scratch load and speed as well as their empirical modelling. This way, the overall scratch resistance of the bilayer coatings could be usefully predicted on a broad range of operational conditions, thus providing helpful indications to paint manufacturers and coaters on how to best deal with the application of metal flake powders.

Progress in Organic Coatings, 2009

Electrostatic spray deposition (ESD) of aesthetic and protective low curable transparent powder c... more Electrostatic spray deposition (ESD) of aesthetic and protective low curable transparent powder coatings onto carbon fibre-reinforced epoxy composites (i.e., carbon laminates) is the matter of the present investigation. An original environment friendly pretreatment of the substrate, based on fluidized bed peening of glass beads followed by a moderate temperature oven baking, has been proposed. Then, the influence of ESD operational

Optics and Lasers in Engineering, 2010

Heat treatment of ceramic-reinforced aluminium matrix composites (AMCs) using a high-power diode ... more Heat treatment of ceramic-reinforced aluminium matrix composites (AMCs) using a high-power diode laser (HPDL) was investigated. AMCs were treated by irradiation with laser beams of different power and scanning speeds. This resulted in significant changes in the overall appearance and microstructure of the composite material. Contact gauge profilometry and combined SEM-EDXS and XRD analyses were performed to investigate the relationship between changes in the morphology and microstructure to the amount of laser energy delivered. Vickers microhardness and tribological tests were performed to identify changes in the local mechanical properties of the composite material. Laser treatment often improves the properties of AMCs, although setting of the operational parameters is crucial. In fact, small deviations in power and/or scan speed can severely damage the material, leading to deterioration of the microstructure and overall mechanical behaviour.

Surface and Coatings Technology, Aug 1, 2006

A neural network approach is used to model a paint stripping process performed using a 1.5 kW con... more A neural network approach is used to model a paint stripping process performed using a 1.5 kW continuous diode laser source on an aluminum substrate coated with approximately 80 μm of a hybrid epoxy-polyester resin. Two different coating colors, namely RAL 8087 (dark) and RAL 1013 (bright), are examined in order to analyze the influence of the difference in absorption of the laser energy by the surface on process.

Progress in Organic Coatings, Dec 1, 2006

This paper deals with the analysis of the evolution of the surface morphology of metal substrates... more This paper deals with the analysis of the evolution of the surface morphology of metal substrates coated with high-performance thermoplastic powders, namely PPA 571 H, by using electrostatic fluidized bed (EFB) process. Attention has been particularly focused on the relationship between baking time and temperature of EFB coated substrates and the morphological characteristics of the resulting polymeric films.

International Journal of Refractory Metals and Hard Materials, 2015

ABSTRACT The present work deals with the post-treatment of thermally-sprayed WC–Co/NiCr coatings ... more ABSTRACT The present work deals with the post-treatment of thermally-sprayed WC–Co/NiCr coatings deposited by (High Velocity Oxygen Fuel) HVOF on a cylindrical substrate in AA 6082 T6 aluminium alloy with a High Power Diode Laser (HPDL). Laser operational parameters, especially laser power and scan rate, were investigated to find the best settings to improve the mechanical response of the WC–Co/NiCr coatings, preventing the onset of surface damage. Visual appearance and morphology of the coatings were investigated by contact gauge profilometry and scanning electron microscopy. The material microstructure was studied by combined scanning electron microscopy and energy dispersive X-ray spectroscopy. Hardness and wear resistance were analysed by instrumented indentation tests. Appropriate combinations of laser parameters were found to enhance significantly the mechanical performance of the WC–Co/NiCr coatings, whose structure was dense, compact and uniform, with hardness and wear endurance highly improved. In contrast, extreme irradiation densities of the laser beam should be carefully avoided to reduce the onset of defectiveness as wide fractures and/or additional porosities inside the thermally sprayed material.

Journal of Coatings Technology and Research, 2014

In the present investigation, scratch resistance, chemical inertness and corrosion resistance of ... more In the present investigation, scratch resistance, chemical inertness and corrosion resistance of methyl phenyl polysiloxane coatings on Fe 430 B structural steel with or without an organo-silane intermediate layer were analyzed. The role of Al-Mg pigments dispersed in the resin was studied, too. The high molecular weight of the polysiloxane resin ensures good adhesion to the substrate, low porosity and high mechanical stability. The good ductility and low steric hindrance of the methyl groups coupled with the chemical inertness of the phenyl groups yields coatings with utmost endurance to aggressive chemicals and, above all, suitable as corrosion retardants on sensitive steel substrates. Lastly, the dispersion in the resin of particles, which act as corrosion inhibitor, as well as the interposition of organo-silane layers between substrate and polysiloxane resin can improve further the potentiality of the designed barrier coatings.

Engineering Science and Technology, an International Journal, 2014

Drag finishing of brass (Cu-30 wt.% Zn) rings using fluidized abrasives, which is a new finishing... more Drag finishing of brass (Cu-30 wt.% Zn) rings using fluidized abrasives, which is a new finishing technology, is comparatively evaluated with centrifugal disk finishing. The comparison was performed by selecting the same abrasive granulates of two different sizes and operating the equipment for the same processing time or at their respective maximum speeds. The experimental analysis investigated the change in workpiece morphology, material removal during finishing and dimensional accuracy. The results showed that each of the types of equipment investigated in the study were capable of a high finishing performance with a relatively short processing time. However, fluidized bed assisted drag finishing was more effective than centrifugal disk finishing in both the achievable quality of the processed parts and reduced processing time. In contrast, centrifugal disk finishing was preferable whenever low erosion and stringent dimensional tolerances were demanded.

Wear, 2011

A novel method using a high power diode laser to selectively remove cobalt binder from the outerm... more A novel method using a high power diode laser to selectively remove cobalt binder from the outermost layer of Co-cemented tungsten carbide (WC-Co 5.8 wt.%) is hereby discussed. A continuous 940-nm wavelength diode laser source at power of 600-1500 W and scanning speed of 1 mm/s was used to perform the thermal treatments. Hot Filament-Chemical Vapour Deposition (HF-CVD) was then used to deposit PolyCrystalline Diamond (PCD) coatings. Increasing the laser fluence, Co-binder was progressively and selectively evaporated from the WC-Co substrate. The selective removal of the Co-binder from the outermost layer of WC-Co induces a significant corrugation of the substrate, very promising to deposit on it high quality diamond with improved adhesion. Indeed, too much high laser fluence must be avoided, as it would tend to induce the resintering or the local melting of the tungsten carbide grains.

Manufacturing Letters, 2013

Abrasive Fluidized Bed (AFB) finishing of cobalt-chromium coatings is investigated. Cylindrical m... more Abrasive Fluidized Bed (AFB) finishing of cobalt-chromium coatings is investigated. Cylindrical metal components coated by High Velocity Oxygen Fuel (HVOF) with Stellite 6 were machined, while rotating at high speed in a bed of suspended Al 2 O 3 abrasives. The interaction between abrasives and coatings was analyzed varying the machining time, abrasive size and rotational speed. The morphology and dimensional stability of the machined parts was monitored by microscopy, profilometry and dimensional analysis. AFB is able to smoothen the morphology of the Stellite 6 coatings, preserving their dimensional accuracy. This makes AFB a promising technique in the reprocessing of hard coatings.

International Journal of Material Forming, 2010

In this paper, morphological and thermal effects induced on sintered bronze substrates by diode l... more In this paper, morphological and thermal effects induced on sintered bronze substrates by diode laser polishing are investigated. The influence of laser power and interaction time was looked into. The evolution of surface morphology was evaluated by scanning electron microscopy and contact-gauge profilometry. Maximum depth of the groove generated by laser on the material was related to amplitude, spacing and hybrid roughness parameters. Experimental results show a decrease in roughness of ~ 50% is reachable if out of tolerance of ~ 200 μm is acceptable. Particular efforts were dedicated to understand the mechanisms involved during the laser treatment and the way by which the final surface morphology was established. In this respect, a thermographic analysis was performed on treated sample to evaluate variations in thermal effusivity. Accordingly, a preliminary experimental model was proposed to approximate the real operational conditions and predict the most promising settings of the laser system aimed at improving the surface finishing of the metal substrates.

Tribology International, 2013

The development of effective coating systems that offer high protection against erosioncorrosion ... more The development of effective coating systems that offer high protection against erosioncorrosion is of utmost importance in several industrial sectors. Such a coating class is typically designed to provide an effective barrier against aggressive environments combined with cathodic protection. The adherence to the substrate ensures full performance and reliability of the coatings during service. In the present investigation, the scratch response of single-and multi-layered composite coatings made from superimposed layers of a modified phenyl-methyl silicone resin and of aluminum-magnesium (Al-Mg 4.5 wt.%) metallic powders was investigated. The applied loads, the contact conditions between the indenter and coating surface and the sliding speeds were analyzed, and empirical models were developed accordingly. The scratch response of the composite coatings was mapped according to the testing conditions, thus providing a useful instrument for designers and practitioners.

Surface and Coatings Technology, 2006

This paper deals with a primerless electrostatic spray deposition process (ESD) for coating therm... more This paper deals with a primerless electrostatic spray deposition process (ESD) for coating thermoplastic (PA66) substrates using epoxypolyester, metallic epoxy-polyester, and epoxy powder paint. A novel and never before used pretreatment system, based on a low speed cold spray of fine copper powders, applied a thin conductive film on the plastic substrate, which made the ESD possible.

Surface and Coatings Technology, 2006

This paper deals with an electrostatic spray deposition (ESD) process of 'self organizing' TiO 2 ... more This paper deals with an electrostatic spray deposition (ESD) process of 'self organizing' TiO 2 -epoxy powder paints on metal substrates. The first part of the paper focuses on analyzing the influence of both electrical and aerodynamic operational parameters on ESD process. Design of experiments (DOE) was used to plan experimental trials. ANOVA tables were calculated and used as support instruments to interpret the experimental findings and to understand physical phenomena involved in the deposition process as well as the role of TiO 2 . As a result, several process maps were produced which report consistent trends in coating thickness versus operational parameters. Best deposition conditions could therefore be deduced. Initial attempts to produce 'self-organizing' TiO 2 -based gradient coatings are also discussed.

Surface and Coatings Technology, 2006

A neural network approach is used to model a paint stripping process performed using a 1.5 kW con... more A neural network approach is used to model a paint stripping process performed using a 1.5 kW continuous diode laser source on an aluminum substrate coated with approximately 80 μm of a hybrid epoxy-polyester resin. Two different coating colors, namely RAL 8087 (dark) and RAL 1013 (bright), are examined in order to analyze the influence of the difference in absorption of the laser energy by the surface on process.

Surface and Coatings Technology, 2008

This paper deals with the development and application of a new technique, Fast Regime-Fluidized B... more This paper deals with the development and application of a new technique, Fast Regime-Fluidized Bed Machining (FR-FBM), for the easy-to-automate finishing of as-deposited Atmospheric Plasma Spraying (APS) TiO 2 coatings on AISI 1040 steel substrates. The effects of leading FBM ...

Surface and Coatings Technology, 2011

The scratch performance of powder-coated substrates depends on many factors, including the coatin... more The scratch performance of powder-coated substrates depends on many factors, including the coating material and thickness, the deposition techniques, and the characteristics of the baking processes. In the present investigation, two thermoplastic (PPA571, an alloy of acid-modified polyolefins) and thermoset (TGIC-free, transparent, bronze-pigmented polyester) organic powders were deposited onto flat aluminium substrates by the 'hot dipping' fluidised bed and electrostatic spray coating technologies. In the former technology, the metal substrates were pre-heated to 300°C before being dipped in the fluidised bed and powder coated. In the latter technology, after electrostatic painting, the coated substrates were submitted to a curing process for 20 min at 170°C to allow the formation of continuous films. The resulting coatings differed in morphology, thickness and adhesion strength. The scratch responses of the coatings were evaluated by progressive-mode scratch tests. Different contact conditions between the scratching geometry and the coating surface were analysed using three conical (Rockwell C) diamond indenters with tip radii of 100, 200 and 800 m. Electrostatically sprayed thermoset coatings showed a better overall scratch resistance with minor deformation events and damage of a lesser extent compared to the thermoplastic coatings. On the contrary, the thermoplastic coatings displayed very singular scratch properties regardless of the deposition process, having the largest deformation events and most massive interfacial rupture.

Progress in Organic Coatings, 2009

The knowledge of the properties of the coatings in terms of scratch and wear resistance is of par... more The knowledge of the properties of the coatings in terms of scratch and wear resistance is of paramount importance in order to prevent the formation of severe damages. Nonetheless, dealing with the evaluation scratch or wear resistance of an organic coating can be troublesome. They can be strongly dependent on the status of the organic material as well as on the contact condition, applied load and strain rate. Besides, reliable responses cannot be achieved if an appropriate experimental design and a combined usage of proper equipments is not scheduled. In this respect, the present analysis deals with the application of variable speed and load scratch tests to characterize the scratch response and wear resistance of bilayer metal flakes powder coatings. Experimental findings allowed the achievement of consistent trends of the deformation response vs. curing temperature, scratch load and speed as well as their empirical modelling. This way, the overall scratch resistance of the bilayer coatings could be usefully predicted on a broad range of operational conditions, thus providing helpful indications to paint manufacturers and coaters on how to best deal with the application of metal flake powders.

Progress in Organic Coatings, 2009

Electrostatic spray deposition (ESD) of aesthetic and protective low curable transparent powder c... more Electrostatic spray deposition (ESD) of aesthetic and protective low curable transparent powder coatings onto carbon fibre-reinforced epoxy composites (i.e., carbon laminates) is the matter of the present investigation. An original environment friendly pretreatment of the substrate, based on fluidized bed peening of glass beads followed by a moderate temperature oven baking, has been proposed. Then, the influence of ESD operational