Influence of grain size on the wear behavior of CVD diamond coatings in micro-EDM

Friction and wear performance of austenite stainless steels have been extensively studied and show a close relationship with the friction-induced martensitic transformation. However, how the grain size and associated friction-induced martensitic transformation behavior affect the tribological properties of austenite steels have not been systematically studied. In this work, dry sliding tests were performed on an AISI 304 stainless steel with a grain size ranging from 25 to 92 μm. The friction-induced surface morphology and microstructure evolution were characterized. Friction-induced martensitic transformation behavior, including martensite nucleation, martensite growth and martensite variant selection and its effect on the friction and wear behavior of the 304 stainless steel were analyzed. The results showed that both the surface coefficient of friction (COF) and the wear rate increase with the grain size. The COF was reduced three times and wear rate was reduced by 30% as the grain size decreased from 92 to 25 μm. A possible mechanism is proposed to account for the effect of grain size on the tribological behavior. It is discussed that austenite steel with refined grain size tends to suppress the amount of friction-induced martensitic transformed and significantly alleviates both the plowing and adhesive effect during dry sliding.

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Self-mated tribological systems based on multilayer micro/nanocrystalline CVD diamond coatings

Wear ◽

10.1016/j.wear.2013.03.049 ◽

2013 ◽

Vol 303 (1-2) ◽

pp. 225-234 ◽

Cited By ~ 23

Author(s):

E. Salgueiredo ◽

C.S. Abreu ◽

M. Amaral ◽

F.J. Oliveira ◽

J.R. Gomes ◽

...

Keyword(s):

Cvd Diamond ◽

Diamond Coatings

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Fatigue Strength and Wear Behavior of NCD and MLD Diamond Coatings Characterized by Different Level of Residual Stresses after Annealing

Defect and Diffusion Forum ◽

10.4028/www.scientific.net/ddf.404.39 ◽

2020 ◽

Vol 404 ◽

pp. 39-44

Author(s):

Georgios Skordaris ◽

Tilemachos Kotsanis ◽

Apostolos Boumpakis ◽

Fani Stergioudi

Keyword(s):

Fatigue Strength ◽

Residual Stresses ◽

Diamond Film ◽

Wear Behavior ◽

Critical Issue ◽

Film Structure ◽

Diamond Coatings ◽

Coated Tool ◽

Cutting Processes ◽

Cemented Carbide Tools

Nano-composite (NCD) and multi-layered (MLD) diamond coatings deposited on cemented carbide tools are often applied in machining of non-ferrous materials. A critical issue for their wear behavior, especially in cutting processes in which interrupted repetitive loads are applied such as milling, is the fatigue strength. The latter parameter is significantly affected by the level of residual stresses in their diamond film structure. For investigating such an issue, untreated as well as annealed for 8h vacuum NCD and MLD coatings of the same thicknesses were produced. Inclined impact tests supported by appropriate FEA models were conducted for calculating the level of the residual stresses and for determining the critical impact force for the fatigue damage after 106 impacts. Moreover, the wear behavior of diamond coated inserts was investigating in milling aluminum foam. According to the attained results, the reduction of the residual stresses in the diamond film structure contributes to a significant increase of the fatigue strength and coated tool life for both examined cases. Moreover, due to the enhanced tribological properties of NCD films, an improved wear behavior is registered compared to the MLD ones, when both coatings possess the same level of residual stresses.

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Wear Behaviour of Two Different Cemented Carbide Grades in Turning 316 L Stainless Steel

Materials Science Forum ◽

10.4028/www.scientific.net/msf.941.2367 ◽

2018 ◽

Vol 941 ◽

pp. 2367-2372 ◽

Cited By ~ 1

Author(s):

Sara Saketi ◽

Ulf Bexell ◽

Jonas Östby ◽

Mikael Olsson

Keyword(s):

Grain Size ◽

Stainless Steel ◽

Wear Resistance ◽

Wear Behavior ◽

Cutting Tools ◽

Cemented Carbide ◽

Wear Behaviour ◽

Binder Phase ◽

Mechanical Wear ◽

Cutting Insert

Cemented carbides are the most common cutting tools for machining various grades of steels. In this study, wear behavior of two different cemented carbide grades with roughly the same fraction of binder phase and carbide phase but different grain size, in turning austenitic stainless steel is investigated. Wear tests were carried out against 316L stainless steel at 180 and 250 m/min cutting speeds.The worn surface of cutting tool is characterized using high resolution scanning electron microscopy (SEM), Energy dispersive X-ray spectroscopy (EDX), Auger electron spectroscopy (AES) and 3D optical profiler.The wear of cemented carbide in turning stainless steel is controlled by both chemical and mechanical wear. Plastic deformation, grain fracture and chemical wear is observed on flank and rake face of the cutting insert. In the case of fine-grained, the WC grains has higher surface contact with the adhered material which promotes higher chemical reaction and degradation of WC grains, so chemical wear resistance of the composites is larger when WC grains are larger. The hardness of cemented carbide increase linearly by decreasing grain size, therefore mechanical wear resistance of the composites is larger when WC grains are smaller.

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Mechanical wear behavior of nanocrystalline and multilayer diamond coatings on temporomandibular joint implants

Journal of Materials Science Materials in Medicine ◽

10.1023/b:jmsm.0000032817.05997.d2 ◽

2004 ◽

Vol 15 (7) ◽

pp. 773-777 ◽

Cited By ~ 58

Author(s):

Malesela J. Papo ◽

Shane A. Catledge ◽

Yogesh K. Vohra ◽

Camilo Machado

Keyword(s):

Temporomandibular Joint ◽

Wear Behavior ◽

Diamond Coatings ◽

Mechanical Wear ◽

Joint Implants

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Analysis of Interlayer between WC–Co and CVD Diamond Film

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.375-376.92 ◽

2008 ◽

Vol 375-376 ◽

pp. 92-96 ◽

Cited By ~ 5

Author(s):

Wen Zhuang Lu ◽

Dun Wen Zuo ◽

Min Wang ◽

Feng Xu

Keyword(s):

Cutting Tools ◽

Chemical Vapor ◽

Cvd Diamond ◽

Diamond Coatings ◽

X Ray Diffraction ◽

Raman Scattering Spectroscopy ◽

Electron Probe Micro Analyzer ◽

Mechanical Bond ◽

Cvd Diamond Coating ◽

Better Than

Electroplated Cr, Ni and Cu were used as interlayer for chemical vapor deposition (CVD) diamond coating on WC–Co cemented carbide cutting tools. The electroplated interlayers were studied by Scanning Electron Microscope (SEM), Electron Probe Micro Analyzer (EPMA) and X-ray diffraction (XRD). The CVD diamond coatings were studied by SEM and Raman Scattering Spectroscopy (Raman). The experimental results show that there is diffusion bonded interface between electroplated layer and WC-Co substrate after H plasma treatment, the bond between electroplated layers and WC-Co substrate changes from mechanical bond to metallurgical bond and the adhesion becomes stronger. Electroplated Cr interlayer forms new phases of Cr3C2 and Cr7C3 under CVD conditions, while electroplated Ni and Cu interlayers do not form carbides under CVD conditions. Cr carbides have good chemical compatibility to diamond, and they are propitious to diamond nucleation and growth during the deposition period. The diamond crystal microstructure, diamond quality and adhesion on Cr interlayer are better than those on electroplated Ni and Cu interlayers.

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