Formation reasons and control measures of abnormal oscillation marks for 10B21 cold-heading steel billets
FU Da-chao1, WEN Guang-hua1, LIU Yao-zong2, TANG Ping1
1. College of Materials Science and Engineering, Chongqing University, Chongqing 400044, China; 2. Tube, Pipe and Bar Business Unit, Baoshan Iron and Steel Co., Ltd., Shanghai 201900, China
Abstract:In order to solve the problems of deep and bending oscillation marks on the surface of billet during continuous casting of 10B21 cold-heading steel produced by a steel mill in china, the characteristics of abnormal oscillation mark on the surface of billet were firstly observed by metallographic microscope, and then the formation reasons of abnormal oscillation mark were analyzed by combining with the actual production conditions. Finally, the process optimization measures to adjust the oscillation parameters and electromagnetic stirring parameters of the mould were proposed and the production tests were carried out. The production test results indicated that the problem of the abnormal oscillation mark on the surface of billet was solved after the adjustment of process parameters, the oscillation mark on the surface of billet become straight and regular, the depth was obviously shallower, the austenite grain size at the oscillation mark decreased obviously, and the surface crack of billet was significantly reduced.
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