Experimental Study on Surface Integrity of Ti-6AI-4V in High Speed Side Milling

• Published in: 天津大学学报：英文版 2012, Vol.18 (3), p.206-212
• Main Author: 杨晓勇 任成祖 王焱 陈光
• Format: Article
• Language: English
• ISSN: 1006-4982; 1995-8196

Aiming at the surface integrity of titanium alloy Ti-6Al-4V in high speed side milling, a series of side milling tests were carried out with uncoated carbide milling cutter at various milling speeds. Surface roughness, residual stress, subsurface microstructure and microhardness variations were investigated. The surface roughness measurement results present that the milling speed from 80 to 120 m/rain fails to produce better and more stable roughness values compared with the result obtained from 320 to 380 m/min. The residual stresses in the feed direction and axial depth of cut direction are in similar trends for the two milling speed levels mentioned above. Moreover, the residual stress pro- duced at 320 to 380 m/min is lower and more stable than that at 80 to 120 m/min. The microstructure analysis shows that the volume offl phase in the near surface becomes smaller and the deformation offl phase in the near surface be- comes obvious with the increase of the milling speed. Subsurface microhardness variation was observed down to 200μm below the machined surface at 80 to 120 m/min and down to 160 μm at 320 to 380 m/min. It is concluded that better surface integrity and higher material removal rate can be obtained at 320 to 380 m/rain than at 80 to 120 m/min.