P92钢高温拉伸断口形貌的研究.pdf

第43卷第4期
材料工程
2015年4月第85-91页
Journal of Materials Engineering
Apr.2015pp.85-91
P92钢高温拉伸断口形貌的研究
High-temperature Tensile Fracture
Morphology of P92 Stee.
赵勇桃,董俊慧,张韶慧2,刘宗昌2,李文学2
(1内蒙古工业大学材料科学与工程学院,呼和浩特010051;
2内蒙古科技大学材料与治金学院,内蒙古包头014010)
ZHAO Yong-
DONG Jun-hui, ZHANG Shao-hi
LIU Zong-chang, LI Wen-xue
(1 School of Materials Science and Engineering, Inner Mongolia
University of Technology, Hohhot 010051, China 2 School of
Materials and Metallurgy, Inner Mongolia University of Science
and Technology, Baotou 014010, Inner Mongolia, China
摘要:采用热模拟法进行600~1300℃温度区间P92钢的高温拉伸实验。利用SEM,LSCM对不同拉伸温度下的断口
形貌及近断口组织进行分析,并对P92钢的力学性能进行研究。结果表明:P92钢拉伸时,抗拉强度由467.32MPa下降
到24.32MPa,屈服强度由56.88MPa下降到1.07MPa;不同拉伸温度下,断口表现以韧性断裂为主,韧性与脆性特征共
存的现象。在600~900℃时,P92钢发生了动态回复过程,断口形貌表现为韧窝特征。冷却至室温,P92钢近断口处组
织均为马氏体十残余奥氏体组织+M1C3+MC+M3C6+MC+M3C型碳化物。随着温度升高,P92钢发生了动态再结
晶,断口形貌以塑孔为主。P92钢近断口处组织为马氏体十残余奥氏体组织十MC+M。C型碳化物
关键词:P92钢;断口形貌;高温拉伸
doi:10.11868/j.issn.1001-4381.2015.04.015
中图分类号:TG142.1文献标识码:A文章编号:1001-4381(2015)04-0085-07
Abstract: High temperature tensile tests of P92 steel were carried out at 600-1300C by means of ther-
mal simulation method. The fracture morphology and microstructure near fracture at different tensile
temperatures were analyzed by SEM and LSCM, and the mechanical properties of P92 steel were in
vestigated. The results indicate that tensile strength decreases from 46732MPA to 24. 32MPA, and
yield strength decreases from 56.88MPA to 1.07MPA. The rupture is mainly ductile rupture with duc
tile and brittle characteristics co-existing. Dynamic recovery occurs with P92 steel at 600-900C, and
the fracture is mainly dimple. The microstructure near fracture of P92 steel is martensite+residua
austenite+M, Ca +MC+M2s Cs +M.C+M, C after cooling down to the room temperature. With the
increasing of the temperature, dynamic recrystallization occurs with P92 steel, and the fracture is
mainly plastic hole. The microstructure is martensite residual austenite+MC+M,C carbides
Key words: P92 steel; fracture morphology; high temperature tensile
近年来为解决日益突出的能源短缺及环境污染问行为1+15],而热加工过程中的变形行为、组织演化、断
题,高效率的超高临界压发电在国际上成为热门话题口形貌还没有详尽的报道。本工作通过研究高温条件
之一。其中铁素体耐热钢P92以其优良的综合性能下P92钢的热变形行为,包括动态回复、动态再结晶
而成为超高临界压发电厂锅炉管用钢的首选材料,并行为、断口组织、断裂机制、高温强度变化规律等,为
得到广泛的应用。P92钢属于多组元强化回火马P92钢的生产成型及生产工艺优化提供参考。
氏体钢,因多种合金元素存在于钢中,在热加工过程中
组织演化非常复杂?,因此很难确定合适的热加工工1实验材料与方法
艺制度。到目前为止,许多P92钢的报道都集中在强
化机制[6-]、时效析出行为91?、蠕变性能-、腐蚀
实验材料为P92钢,加工成尺寸为中10mmX