轻质中锰钢局部变形带的研究现状  

Advances in Research of Local Deformation Zone inLightweight Medium Manganese Steels

作　　者：周宇航 杨明维 冯运莉 ZHOU Yuhang;YANG Mingwei;FENG Yunli(Key Laboratory of the Ministry of Education for Modern Metallurgy Technology,College of Metallurgy and Energy,North China University of Science and Technology,Tangshan 063210,Hebei,China)

机构地区：[1]华北理工大学冶金与能源学院,现代冶金技术教育部重点实验室,河北唐山063210

出　　处：《材料导报》2024年第21期248-255,共8页Materials Reports

基　　金：国家自然科学基金(51974134);河北省科技重大专项(21281008Z)。

摘　　要：轻质中锰钢是第三代先进高强钢的代表,在变形过程中由于C、Mn、Al等合金元素的存在其可动位错经历被固溶原子和C-Mn原子团钉扎和脱扎的过程,从而在应力-应变曲线上呈现出吕德斯(Lüders)带和Portrvin-Le Chatelier(PLC)带这两种最典型的局部变形带,导致材料表面质量降低,对后续加工使用不利。目前,消除Lüders带和PLC带引起的表面缺陷的常用方法是在成形前对材料施加小的预应变或者调控材料的组织。然而这种方法只适用于经历小Lüders带应变和PLC效应的材料,因此寻求一种更为有效的延迟或消除Lüders带与PLC带的方法显得极其重要。本文从发生机理入手,讨论预应变、退火温度、退火时间等工艺和合金元素对上述两种局部变形带的影响,进而从晶粒尺寸、组织形貌、位错密度等微观角度总结减弱或加剧二者的具体机制,并着重解释不同成分与热处理工艺对C-Mn原子团形成、移动速率和与位错交互时间的影响以及抑制局部变形带的形成与拓展的作用。随后根据已有研究提出的不同解决方案,结合上述宏观与微观影响因素,展望了未来该领域研究的发展。Lightweight medium manganese steels are a representative of the third generation advanced high-strength steels.They have been found to exhibit Lüders bands and Portevin-Le Chatelier(PLC)bands on their stress-strain curves during deformation.The two types of bands originate from the presence of alloying elements such as C,Mn,Al,and can be regarded as a symbol of interaction between dislocations being pinned and depinned by C-Mn atomic group.Therefore these bands lead to surface defects that reduce the quality of the materials and are unfavorable for subsequent processing.Nowadays,the commonly used methods to eliminate surface defects caused by Lüders bands and PLC bands involve applying a small pre-strain to the material or controlling its microstructure before forming.But this approach is only effective for materials experiencing low strains from Lüders bands and PLC effects,and it has become highly important to seek a more effective method to delay or eliminate Lüders bands and PLC bands.This paper discusses the influencing factors of pre-strain,annealing temperature,annealing time length,and alloying elements on Lüders bands and PLC bands,starting with an outline to the underlying occurrences causing these bands.It further summarizes the specific reasons for mitigating or intensifying these bands from a microscopic perspective,including grain size,microstructure morphology,and dislocation density.The paper also emphasizes the effects of different alloy compositions and heat treatment processes on the formation,migration rate,and interaction time of C-Mn atomic group with dislocations,as well as the corresponding utilities in suppressing the formation and propagation of local deformation zone.It ends with a prospective discussion about the future development of the field based on the solutions provided in the published researches,and considering the aforementioned macroscopic and microscopic influencing factors.

关 键 词：轻质中锰钢 Lüders带 PLC带 C-Mn原子团 TRIP效应 

分 类 号：TG142[一般工业技术—材料科学与工程]