Study of a Novel Ceramic Tool Performance in the Machining of Ti-6Al-7Nb Alloys

Abstract

Considering their distinctive properties, titanium alloys are used in foremost industries, including the aeronautic, automotive and biomedical industries. The reduced machinability of titanium alloys is due to their low thermal conductivity and high plasticity behavior. In the biomedical sector, one of the most studied alloys is Ti-6Al-4V. In the case of the Ti-6Al-7Nb alloy, scarce investigations are identified, related to machinability studies. The machining of Ti-6Al-7Nb alloy requires the development of new tools with higher properties, which provide better performance. The objective of this study is to present the experimental results related to a novel ceramic cutting tool, in terms of cutting tool life and productivity, in the machining of Ti-6Al-7Nb alloy. A turning operation of a 25 mm diameter bar was performed; the cutting speed was varied in three levels. The results showed the high performance of this type of tools, from the point of view of machinability. The values of the obtained cutting forces are found in the ranges reported by the consulted literature using ceramic tools. The surface roughness values were considered appropriate, taking into account that the tool is recommended for roughing and semi-finishing operations. The most relevant results were obtained in terms of productivity, considering that the performance is 2.53 times higher than the presented in similar works.

Experimental investigation and optimization of hybrid turning of Ti6Al7Nb alloy under nanofluid based MQL by TOPSIS method

“…Based on the literature review, the MQL method used in this study was conducted with a vegetable-based cutting oil with a thermal conductivity of 0.5-1 W/m.K [18]. In contrast, graphene is produced from synthetic graphite powder [19] and graphene nanoparticles can exhibit an impressive thermal conductivity of up to 3000-5500 W/m.K [20,21]. Consequently, graphene added nanofluid based MQL (NMQL) is improve heat transfer.…”

“…These properties lead to rapid tool wear and plastic deformation of cutting tools reported by researchers [17,18]. For instance, Risco-Alfonso et al [19] conducted turning exper-iments on Ti-6Al-7Nb alloy using ceramic tools under dry cutting conditions. Their results showed that at the cutting speed of 200 m/min, the tool life was limited to only 6 minutes.…”