Effect of Annealing Process on the Mechanical Properties of X70 Pipeline Steel Teng-wei Zhu, Cheng-liang Miao, Zheng Cheng, Zhipeng Wang, Yang Cui and Fei Li MATEC Web Conf., 186 (2018) 02001 Published online: 06 August 2018 DOI: 10.1051/matecconf/201818602001