Electrical Properties of Half Heusler Coatings Depending on Spray Process

Abstract Microstructure and physicochemical properties of a thermally sprayed coating depend on the dynamics of the particles interacting with the spray jet. This is especially the case for electrical properties. In this study, different spraying processes were used to spray p-type and n-type half-Heusler powders. Thermoelectric powders, Hf20Zr75Ti05CoSb80Sn20 (p-type) and Hf60Zr40NiSn98Sb02 (n-type), were selected due to their interesting electrical properties. The spray processes were evaluated based on coating composition and mechanical property measurements. The only coatings of practical interest were those that were plasma sprayed and they were examined in detail to assess the effect of process parameters on coating properties.

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Deformation of Plasma Sprayed Thermal Barrier Coatings

Volume 4: Manufacturing Materials and Metallurgy; Ceramics; Structures and Dynamics; Controls, Diagnostics and Instrumentation; Education; IGTI Scholar Award; General ◽

10.1115/99-gt-348 ◽

1999 ◽

Author(s):

Ufuk Senturk ◽

Rogerio S. Lima ◽

Carlos R. C. Lima ◽

Christopher C. Berndt

Keyword(s):

Acoustic Emission ◽

Composite System ◽

Coating Properties ◽

Failure Characteristics ◽

Deformation Curves ◽

Metallic Bond ◽

Point Bend ◽

Plasma Sprayed ◽

Thermally Sprayed

The deformation behavior of thermally sprayed partially stabilized zirconia (PSZ) coatings are investigated using Hertzian indentation and four-point bend testing, with in situ acoustic emission monitoring. The experimental deformation curves, together with the corresponding acoustic emission responses and the fracture properties of the material are used in defining the deformation characteristics of the coating (ceramic overlay with metallic bond coal where applicable) and substrate composite system. Experiments are aimed in examining the influence of the bond coat and the coating properties on the form of deformation. Substrate temperature and pauses during spraying are demonstrated to strongly effect the coating properties and the resulting fracture/failure characteristics of the composite system.

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Simulation of thermally sprayed coating properties considering the splat boundaries

IOP Conference Series Materials Science and Engineering ◽

10.1088/1757-899x/1147/1/012026 ◽

2021 ◽

Vol 1147 (1) ◽

pp. 012026

Author(s):

K Bobzin ◽

W Wietheger ◽

H Heinemann ◽

F Wolf

Keyword(s):

Coating Properties ◽

Sprayed Coating ◽

Thermally Sprayed

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Thermally Sprayed Porous PEEK Coating for Biomedical Implants

Journal of Thermal Spray and Engineering ◽

10.52687/2582-1474/116 ◽

2018 ◽

Vol 1 (1) ◽

pp. 32-36

Author(s):

Satish Tailor ◽

◽

N Vashishtha ◽

Ankur Modi ◽

SC Modi ◽

...

Keyword(s):

Orthopedic Implants ◽

Titanium Coating ◽

The Novel ◽

Biomedical Implants ◽

Thermal Spray Process ◽

Spray Process ◽

Plasma Sprayed ◽

Peek Coating ◽

Thermally Sprayed ◽

Highly Porous

The present study reports the novel results of microstructural and mechanical properties of highly porous Polyetheretherketone (PEEK) coating. PEEK is already considered as a material for biomedical implants. A new kind of approach is proposed for manufacturing of highly porous PEEK coating on a dense PEEK coating for orthopedic implants and successfully implemented to create novel biomimetic porous PEEK coating by means of thermal spray process. To imitate the structure of natural bone, as-sprayed top PEEK coating has porosity of more than 60% vol. and pore sizes of 30-80 μm. Mechanical results of dense PEEK coating show that PEEK coating exhibited good strength, hardness (20 HV0.1) and good bonding strength (15 MPa) with the metal substrate. Thermal sprayed porous PEEK coating that can be used for future implants instead of plasma sprayed titanium coating on dense PEEK implants because porous PEEK improves the bone-implant interface joining compared to plasma-sprayed titanium coating on PEEK.

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Experimental Approach to Adhesion between an Alumina Plasma-Sprayed Coating and Polymeric Substrate

Thermal Spray 1996: Proceedings from the National Thermal Spray Conference ◽

10.31399/asm.cp.itsc1996p0239 ◽

1996 ◽

Author(s):

P. Lucchese ◽

R. Jeandin ◽

G. Surdon ◽

A. Delavernme

Keyword(s):

Bond Coat ◽

Surface Preparation ◽

Spray Coating ◽

Thermal Spray Coating ◽

Fiber Layer ◽

Bond Coats ◽

Reinforced Polymer ◽

Sprayed Coating ◽

Plasma Sprayed ◽

Thermally Sprayed

Abstract Thermal spray coating of fiber reinforced polymer (FRP) components has a high development potential to improve their wear, erosion and corrosion resistance. This paper deals with the optimization of plasma spraying conditions of alumina onto a FRP substrate, including the study of surface preparation. The so-called "Atmosphere and Temperature Controlled Process (ATC, patented by CEA)" was used to maintain the substrate temperature at a rather low level, i.e. near room temperature. Various surface preparation processes such as grit blasting, cleaning using the plasma torch and pre-coating with an intermediate bond coat were tested. The latter was shown to improve adhesion between the coating and the substrate significantly, when using 2 types of bond coats. One consisted of an additionnal fiber layer directly stuck to the substrate, the other of an intermediate thermally-sprayed PEEK layer. Results of adhesion tests were discussed in the light of interface characterization. Using a PEEK bond coat led to an adhesion strength between alumina and the substrate 3 times better than that for the material without any bond coat.

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Deformation of Plasma Sprayed Thermal Barrier Coatings

Journal of Engineering for Gas Turbines and Power ◽

10.1115/1.1287493 ◽

2000 ◽

Vol 122 (3) ◽

pp. 387-392 ◽

Cited By ~ 7

Author(s):

Ufuk Senturk ◽

Rogerio S. Lima ◽

Carlos R. C. Lima ◽

Christopher C. Berndt

Keyword(s):

Acoustic Emission ◽

Bond Coat ◽

Composite System ◽

Coating Properties ◽

Failure Characteristics ◽

Deformation Curves ◽

Point Bend ◽

Plasma Sprayed ◽

Thermally Sprayed

The deformation behavior of thermally sprayed partially stabilized zirconia (PSZ) coatings are investigated using Hertzian indentation and four-point bend testing, with in situ acoustic emission monitoring. The experimental deformation curves, together with the corresponding acoustic emission responses and the fracture properties of the material are used in defining the deformation characteristics of the coating (ceramic overlay with metallic bond coat where applicable) and substrate composite system. Experiments are aimed in examining the influence of the bond coat and the coating properties on the form of deformation. Substrate temperature and pauses during spraying are demonstrated to strongly effect the coating properties and the resulting fracture/failure characteristics of the composite system. [S0742-4795(00)02503-5]

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Thermally Sprayed Coating Composites for Film Heating Devices

Advances in Science and Technology ◽

10.4028/www.scientific.net/ast.45.1230 ◽

2006 ◽

Vol 45 ◽

pp. 1230-1239 ◽

Cited By ~ 7

Author(s):

Andreas Killinger ◽

Rainer Gadow

Keyword(s):

Thermal Spray ◽

Spray Deposition ◽

Deposition Process ◽

Medium Temperature ◽

Thermal Spray Process ◽

Spray Process ◽

Heating Device ◽

Layer Structures ◽

Sprayed Coating ◽

Thermally Sprayed

Direct heated systems in white goods for medium temperature applications (approx. 250° -350° C) can be applied onto glass, glass ceramic and metal substrates by means of thermal spray techniques. Essentially, such a system requires at least two functional layers to work properly: (1) The metal coating that works as the heating element and (2) an insulator coating that electrically separates the substrate from the film heater. Therefore, the heating device combines three materials (substrate, insulator and film heater) with rather different thermophysical properties. An optimized spray deposition process with proper guidance of the heat flow is required to produce coatings that can operate under cyclic thermal load conditions. The paper discusses the influence of thermal spray process parameters as well as the applied spray powders on the electrical properties of the achieved layer structures of the respective insulator and film heater coatings.

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