The Study of Chip Control in Turning Titanium Alloy

• Main Authors: Huajie Zhu, 祝華杰
• Other Authors: Yunn-Shiuan Liao
• Format: Others
• Language: zh-TW
• Published: 2017
• Online Access: http://ndltd.ncl.edu.tw/handle/vrmzx3

碩士 === 國立臺灣大學 === 機械工程學研究所 === 105 === With the development of social productive forces, application of titanium alloys is not only confined to the field of aerospace and military, but also is increasingly being used in the production of all aspects of life. However, because of its unique material properties, we can not get better processing efficiency and lower processing costs. Among all these puzzles, the problem of chip control of Titanium alloys(Ti-6Al-4V) has been troubling the manufacturing industry. Long and tough chips hinder the improvement of processing efficiency, affecting the surface roughness of the workpiece, reducing tool life. This research aims to find a reasonable solution for the chip control of Ti-6Al-4V. First, the cutting forces of Ti-6Al-4V were discussed with the three cutting parameters of feed, depth of cut and cutting speed respectively, comparing to the shape of the chips; Most of the chip shapes are helical. Finally, when the feed rate reaches 0.25mm/rev, chip has the tendency to become C-type breaking chip. the contact distance between the chip and tool face is less than 1mm in common turning conditions. We need to be reduced, to be increased, increase the chip flow angle appropriately and with the design of the Groove-type chip breaker at the same time to guide the chip collision to the flank face. According to this study found that increasing the feed rate appropriately causes increasing; decreasing the cutting speed appropriately causes decreasing, increasing; decreasing depth of cut appropriately causes decreasing, increasing, it is possible to guide the chip collision to the flank face. Finally, it is deduced that if Ti-6Al-4V chip breaks automatically under less than 0.2 mm / rev feed rate, we need the chip breaker width W less than 1.2mm, but the current commercial chip breaker chip breaker width is greater than 1.5mm. So, in dry cutting condition, in the cutting range recommended by the tool manufacturer, Ti-6Al-4V chip is difficult to break automatically.