Microstructure and grindability of as-cast Ti-Sn alloys

In this study, the structure, microhardness, and grindability of a series of binary Ti-Sn alloys with tin contents ranging from 1 to 30 wt% were investigated. Commercially pure titanium (c.p. Ti) was used as a control. The experimental results indicated that all the Ti-Sn alloys showed hcp alpha structure, and the hardness values of the Ti-Sn alloys increased with greater Sn contents, ranging from 246 HV (Ti-1Sn) to 357 HV (Ti-30Sn). Among these Ti-Sn alloys, the alloy with 30 wt% Sn content showed the highest hardness value. The grindability of each metal was found to be largely dependent on the grinding conditions. The addition of Sn to c.p. Ti did contribute to improving the grindability of c.p. Ti. The Ti-Sn alloys with a higher Sn concentration could be ground more readily. The grinding rate of the Ti-20Sn alloy at 1200 m/min was about 2.8 times higher than that of c.p. Ti. Additionally, the grinding ratios of the Ti-10Sn, Ti-20Sn, and Ti-30Sn alloys at 1200 m/min were about 2.8, 2.7, and 3.4 times that of c.p. Ti, respectively. Our research suggests that the Ti-Sn alloys with Sn contents of 10 wt% and greater developed here are good candidates for machining by the CAD/CAM method.