Transactions of Nonferrous Metals Society of China
JOURNAL OF RAILWAY SCIENCE AND ENGINEERING
|Vol. 17 No. 6 December 2007|
（1. School of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001, China; 2. School of Mechatronics Engineering, Harbin Institute of Technology, Harbin 150001, China ）
Abstract:Hot spinning of tubular workpiece of TA15 alloy was conducted on a CNC spinning machine, and the microstructure evolution during hot spinning and annealing was observed and mechanical properties of spun tubes were tested. The results show that with the increase of spinning pass, the fiber microstructure comes into being gradually in axial direction and the circumferential microstructure also stretches obviously along circumferential direction. At the same time, the tensile strength increases and elongation decreases not only in axial direction but also in circumferential direction. When the reduction ratio of wall thickness rises close to or over 40%, tensile strength increases and elongation decreases more rapidly, which means that tubular workpiece of titanium alloy can be strengthened bi-directionally by power spinning. The ductility of spun workpiece of TA15 alloy could be improved by annealing at the temperature no higher than recrystalization temperature with slight decrease of tensile strength.
Key words: TA15 alloy; hot spinning; microstructure evolution; mechanical property; annealing