20MnSi生产高强带肋钢筋HRB500工艺及其组织与性能

Process for Producing HRB500 with 20MnSi and Its Microstructure and Mechanical Properties

讨论了准14mm20MnSi穿水生产HRB500的工艺流程、化学成分、金相组织和力学性能,提出了合理的C含量控制目标。结果表明:准14mm20MnSi穿水生产HRB500钢筋时金相组织为:表层回火M,回火M厚度约为钢筋直径的1/8,中间依次形成B、F+P+B混合组织,心部为细小的F+P,F晶粒度为9.0～9.5级,与热轧钢筋相比,穿水钢筋心部P含量多,F晶粒度提高1.0级,钢筋力学性能符合HRB500的要求,达到了降低生产成本的目的。

The QTB process,chemical composition,microstructure and mechanical property of 14 mm 20MnSi were discussed.The reasonable carbon content was proposed.The results show that microstructure from the surface to the centre of the tested ribbed bar is temper M,B,F ＋ P ＋ B and F ＋ P,respectively;the thickness of the tempered M is about 1/8 diameter of the ribbed bar.The ferrite grain size in the core of the testing ribbed bar is 9.0～9.5 grade.More pearlite forms in the center and the F grain size grade enhances 1.0 level than that of the hot rolled ribbed bar.The mechanical property of the testing ribbed bar qualifies to HRB500 and the production cost reduces.