Wear behaviour of gradient-multilayer diamond coatings deposited on cemented-carbide substrates

Abstract

HFCVD method was used to prepare and characterize single and gradient multi-layered diamond coatings on tungsten carbide. The wear behaviour was evaluated in ambient air, against Si 3 N 4 ceramic balls. The results demonstrated that with the increase of carbon-source concentration from 1% to 5%, the diamond surface grains gradually refined and formed crystal clusters, and the roughness (Ra) of diamond surface decreased from 62.3 to 32.54 nm. Concerning the 100, 300, and 600 nm gradient of multilayer diamond coatings, the roughness Ra was 31.3, 35.6, and 40.5 nm, respectively. The diamond film obtained with 1% CH 4 concentration exhibited poor wear resistance. For higher CH 4 concentration, the abrasion resistance increased gradually. The average friction coefficient of multilayer diamond coatings decreased from 0.052 to 0.023 as the modulated layer thickness increased from 100 to 600 nm. The gradient multilayer structure significantly improved the tribological behaviour.

In-situ-growth of hard-coating, its impact on mechanical performances in cemented-carbides

“…Common coating materials include TiN, Ti(Al, Si)N, and diamond. 15 However, disparities in composition and properties between the substrate and coating materials often lead to residual stresses within the coating, insufficient bonding, and coating delamination or cracking, impacting tool longevity. 16 Another prevalent surface modification approach in the cemented carbide industry is the preparation of graded cemented carbides.…”

Structural analyses of carbon films deposited at different total mass rates in a hot-filament CVD system

“…32 The roughness and wear resistance of the diamond coating was improved by increasing the carbon source. 33 A conductive diamond for the microscope tip was prepared and characterized. 34 The influence of the different total mass flow rates when depositing carbon films still needs to be determined.…”

“…32 The roughness and wear resistance of the diamond coating was improved by increasing the carbon source. 33 A conductive diamond for the microscope tip was prepared and characterized. 34…”