中国激光, 2019, 46 (11): 1102004, 网络出版: 2019-11-09  

等温贝氏体转变对CMnAl-TRIP钢残余奥氏体稳定性及力学性能的影响 下载: 912次

Effects of Isothermal Bainite Transformation on Stability of Retained Austenite and Mechanical Properties of CMnAl-TRIP Steel
作者单位
东北大学轧制技术及连轧自动化国家重点实验室, 辽宁 沈阳 110819
摘要
采用连续退火工艺对CMnAl-TRIP钢进行处理,获得了不同贝氏体区等温温度和不同等温时间下的钢板样品,结合扫描电镜、电子探针、电子背散射衍射、透射电镜、X射线衍射等检测手段对经不同工艺处理后的钢的组织、元素分布及残余奥氏体进行表征,研究了不同贝氏体等温条件下残余奥氏体的稳定性及其对实验钢塑性和加工硬化的影响。结果表明:不同工艺处理后的实验钢的组织均由铁素体、贝氏体、残余奥氏体及少量马氏体组成;随着等温温度从380 ℃升高到420 ℃,残余奥氏体的体积分数逐渐增大,残余奥氏体中碳的质量分数逐渐增大,强塑积逐渐增大;之后随着温度继续升高到460 ℃,残余奥氏体的体积分数逐渐减小,残余奥氏体中碳的质量分数逐渐减小,强塑积逐渐降低;在等温温度为420 ℃时,残余奥氏体的稳定性较高,实验钢的综合力学性能最优,保温时间为180 s时,残余奥氏体的体积分数为10.7%,残余奥氏体中碳的质量分数为1.069%,实验钢的屈服强度为455 MPa,抗拉强度为681 MPa,断后伸长率为31.7%,强塑积达到了21.59 GPa·%。等温时间延长有利于贝氏体转变,增加残余奥氏体的含量及稳定性,提高TRIP钢的综合力学性能。足够多的残余奥氏体是发生TRIP效应的条件,适当的稳定性是提供持续加工硬化、增大钢塑性的保证。
Abstract
A continuous annealing process is used to treat transformation-induced plasticity (TRIP) steel containing carbon, manganese, and aluminum and obtain the steel-plate samples at different temperatures and holding time of isothermal bainite transformation (IBT). Further, the microstructure, element distribution, and retained austenite of the steel treated by different processes have been characterized using scanning electron microscopy, electron probe microanalysis, electron backscattered diffraction, transmission electron microscopy, and X-ray diffraction. The stability of retained austenite under different bainite isothermal conditions and its effects on the plasticity and work hardening of experimental steel are studied. The results denote that the microstructure of experimental steel treated by different processes comprises ferrite, bainite, retained austenite, and small amounts of martensite. With increasing the temperature of IBT from 380 ℃ to 420 ℃, the volume fraction of retained austenite, mass fraction of carbon in retained austenite, and product of tensile strength and elongation increase gradually. As the temperature of IBT further increasing up to 460 ℃, those three parameters decrease gradually. At the IBT temperature of 420 ℃, the stability of retained austenite as well as the comprehensive mechanical properties are observed to be optimal. When the time for holding the temperature of IBT at 420 ℃ is 180 s, the corresponding volume fraction of retained austenite is 10.7%, mass fraction of carbon in retained austenite is 1.069%, yield strength is 455 MPa, tensile strength is 681 MPa, total elongation is 31.7%, and the product of tensile strength and elongation is 21.59 GPa·%. The extension of holding time of IBT can accelerate the bainite transformation, improve the volume fraction and stability of the retained austenite, and enhance the comprehensive mechanical properties of TRIP steel. It is necessary to ensure sufficient volume fraction of the retained austenite to induce the TRIP effect, ensure proper stability during continuous work hardening, and improve the plasticity.

黄慧强, 邸洪双, 张天宇, 闫宁, 龚殿尧. 等温贝氏体转变对CMnAl-TRIP钢残余奥氏体稳定性及力学性能的影响[J]. 中国激光, 2019, 46(11): 1102004. Huiqiang Huang, Hongshuang Di, Tianyu Zhang, Ning Yan, Dianyao Gong. Effects of Isothermal Bainite Transformation on Stability of Retained Austenite and Mechanical Properties of CMnAl-TRIP Steel[J]. Chinese Journal of Lasers, 2019, 46(11): 1102004.

引用该论文: TXT   |   EndNote

相关论文

加载中...

关于本站 Cookie 的使用提示

中国光学期刊网使用基于 cookie 的技术来更好地为您提供各项服务,点击此处了解我们的隐私策略。 如您需继续使用本网站,请您授权我们使用本地 cookie 来保存部分信息。
全站搜索
您最值得信赖的光电行业旗舰网络服务平台!