Influence of hot drawing process on cracking of high nitrogen nickel free austenitic stainless steel wire rod
NING Xiao-zhi1, XING Chang-jun1, YONG Qi-long1, WENG Jian-yin1,2
1.Department for Structural Materials, Central Iron and Steel Research Institute, Beijing 100081, China; 2.Technology Center of FIYTA Group Co., Ltd., Shenzhen 518057, Guangdong, China
Abstract：During developing a high nitrogen and nickel free austenitic stainless steel wire rod, a large number of cracks appeared on the surface of the hot drawn wire rod. The cracking reasons were studied by means of optical microscopy, scanning electron microscopy and energy dispersive spectrometer. It was found that the surface cracks of the wire rod were basically perpendicular to the drawing direction. The cracking occurred on the surface and then developed into the inner. A lot of Cr-rich and N-rich nitrides separated on the surface of the wire rod. The precipitated phase along the grain boundaries would lead to the formation of voids, which could connect each other to form microcracks. After that, the intergranular cracking and fracture occurred. By lengthening the heating zone and increasing the drawing speed, the surface temperature of the wire rod was ensured, the surface cracking was avoided. The high nitrogen nickel free austenitic stainless steel wire rod with high quality was manufactured. Finally, the recommended hot drawing process was given.
宁小智, 邢长军, 雍岐龙, 翁建寅. 热拔工艺对高氮无镍奥氏体不锈钢线材开裂的影响[J]. 中国冶金, 2020, 30(5): 47-50,75.
NING Xiao-zhi, XING Chang-jun, YONG Qi-long, WENG Jian-yin. Influence of hot drawing process on cracking of high nitrogen nickel free austenitic stainless steel wire rod[J]. China Metallurgy, 2020, 30(5): 47-50,75.
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2020, Vol. 30 
