Affiliation: | 1. CNPC Tubular Goods Research Institute, Xi′an 710065, Shaanxi, China 2. Xingtai Polytechnic College,Xingtai 054035, Hebei, China 3. Institute of Metal Research, Academy of Sciences, Shenyang 110016,Liaoning, China 4. Central Iron and Steel Research Institute, Beijing 100081, China |