Wear evaluation of a self-propelled rotary tool when machining titanium alloy IMI 318

Abstract

This paper presents results of a self-propelled rotary tool (SPRT) tipped with round uncoated carbide (WC-Co) inserts in the finish turning of titanium alloy IMI 318. SPRT inserts exhibited superior wear resistance to conventional round and rhomboid-shaped carbides as well as to the rhomboid-shaped physical vapour deposition (PVD) TiN-coated carbide inserts owing to the distribution of the cutting energy along the entire tool edge. The SPRT-tipped inserts suppressed thermally related wear mechanisms at higher speeds beyond the capability of conventional tools. Chipping was the dominant failure mode of the SPRT inserts, resulting from cyclically fluctuating thermal and mechanical shocks induced by the continuous shifting of the cutting edge during machining. A fitted exponential wear model revealed that about 97 per cent of the average flank wear rate of SPRT inserts can be attributed to the joint effect of speed, feed and inclination angle, ε. Tool performance was improved by increasing the inclination angle ε which resulted in a lower machining temperature on account of a higher rotary speed and a lower relative cutting speed during machining. Lower component forces were recorded with SPRT inserts because of the reduced amount of work done in chip formation and lower friction at the rake face.

Performance assessment in hard turning of AISI 1015 steel under spray impingement cooling and dry environment

“…In general, when machining steel with coated carbide tools, different tool wear mechanisms occur, such as abrasion, adhesion, oxidation and even some diffusion, which act simultaneously and in proportions depending mainly on the temperature as suggested by Usui. 10 Ezugwu et al 11 have found that temperature can reach up to 1500°C during machining of stainless steel with carbide tool in conventional lathe. Therefore, water-based fluid is widely used to dissipate the heat in order to reduce the strength of the cutting tool, leading to tool failure by diffusion wear.…”

Experimental Study on Turning With Self-Propelled Rotary Cutting Tool

“…Kishawy and Wilcox [7] studied tool wear and chip formation during hard turning with self-propelled rotary cutting tools and they reported that self-propelled tools showed good resistance to tool wear compared with stationary cutting tools under the same cutting conditions. Ezugwu et al [8] investigated wear evaluation using self-propelled rotary cutting tool in machining of titanium alloy IMI 318 and rotary cutting tool exhibited superior wear resistance to conventional stationary cutting tools. Kishawy et al [9] studied on tool performance and machined surface quality during the machining of aerospace alloys using self-propelled rotary cutting tools and they obtained optimum and safe cutting conditions.…”

The wear model of rotary inserts of knives with self-propelled rotary blade (SPRT) in machining of hardened materials

“…1. Nóż SPRT w imaku narzędziowy tokarki (a), widok strefy skrawania (b) dzonych w kraju i na świecie [2,3,4,5,6] wskazują na potrzebę oparcia takich badań na klasycznych geometrycznych kryteriach zużycia i trwałości narzędzia rejestrowanych na powierzchni natarcia (krater) i przyłożenia ostrza (starcie), przy czym zużycie powierzchni przyłożenia wydaje się częściej stosowanym i przydatniejszym w analizach porównawczych wyników zaczerpniętych z różnych prac [3,4,5,6]. …”