On the diffusion wear of cemented carbide in the turning of 316L austenitic stainless steel

• Published in: Wear Vol. 430-431; p. 202
• Main Authors: Saketi, Sara, Bexell, Ulf, Östby, Jonas, Olsson, Mikael
• Format: Journal Article
• Language: English
• Published: 2019
• Subjects: 316 L austenitic stainless steel; AES; Cemented carbide; diffusion wear; SEM; Steel Forming and Surface Engineering; Stålformning och ytteknik; ToF-SIMS; turning
• ISSN: 1873-2577; 0043-1648
• DOI: 10.1016/j.wear.2019.05.010

The present study focuses on the wear and wear mechanisms of three different cemented carbide grades during orthogonal turning of 316L austenitic stainless steel at different cutting speeds. The influence of WC grain size and cutting speed on the resulting crater and flank wear was evaluated by optical surface profilometry and scanning electron microscopy (SEM). The mechanisms behind the crater and flank wear were characterized on the sub-micrometer scale using high resolution SEM, energy dispersive X-ray spectroscopy (EDS), Auger electron spectroscopy (AES) and time of flight secondary ion mass spectrometry (ToF-SIMS) of the worn cutting inserts and the produced chips. The results show that the wear rate of cemented carbide drastically increases with increasing cutting speed and that the wear is dependent on the WC grain size; i.e. the crater wear decreases with increasing WC grain size while the flank wear increases with increasing WC grain size. High resolution SEM, AES and ToF-SIMS analysis of the worn cemented carbide within the crater and flank wear regions reveal that the degradation of cemented carbide at higher cutting speeds is mainly controlled by diffusion wear of the WC-phase. This is confirmed by ToF-SIMS analysis of the back-side of stainless steel chips which reveals the presence of a 10 nm thin W-containing oxide film. The results are discussed and interpreted in the light of the conditions prevailing at the tool-chip interface.