Investigation of the Damage Mechanism of CrN and Diamond-Like Carbon Coatings on Precipitation-Hardened and Duplex-Treated X42Cr13/W Tool Steel by 3D Scratch Testing
Shiraz Ahmed Siddiqui, Grégory Favaro, Mária Berkes Maros
Abstract
Abstract The present work deals with the characterization of the scratch resistance of two different types of coatings, i.e., chromium nitride (CrN) and diamond-like carbon prepared on X42Cr13/W (1.2083) plastic mold tool steel by physical vapor deposition and plasma-enhanced chemical vapor deposition, respectively. Our study focuses on the influence of the duplex treatment, i.e., plasma nitriding + ceramic coating on the scratch resistance of the tool steel. An advanced 3D scratch testing methodology has been used to investigate the coating adhesion and damage mechanism during scratching. The scratch analysis is completed by ball cratering test and micro-Vickers test to determine the thickness and hardness of the coatings. The test results demonstrate that the applied duplex treatment is an unambiguously advantageous surface technological process which manifests itself in higher loadability and lower sensitivity for cracking of the duplex coatings, increasing the critical forces. The scratch resistance of the combined substrate/coating material system is enhanced by the harder substrate material, providing a better interfacial bonding for both types of the ceramic coatings without changing the basic damage mechanisms.