ECAP制备高强高韧马氏体耐热钢  

HIGH STRENGTH AND HIGH TOUGHNESS HEATRESISTANT MARTENSITIC STEEL PRODUCED BY ECAP

作　　者：张凌义[1] 杨钢[2] 黄崇湘[3] 陈为亮[1] 王立民[2] 

机构地区：[1]昆明理工大学真空冶金国家工程实验室,昆明650093 [2]钢铁研究总院,北京100081 [3]中国科学院金属研究所沈阳材料科学国家(联合)实验室,沈阳110016

出　　处：《金属学报》2008年第4期409-413,共5页Acta Metallurgica Sinica

基　　金：国家高新技术研究发展计划资助项目2002AA302501~~

摘　　要：研究了热轧态1Cr16Co5Ni2MoWVNbN马氏体耐热钢经一道次等径角挤压(ECAP)变形+680℃×2h空冷处理后的微观结构和力学性能.结果表明:经ECAP变形后,马氏体板条大部分已碎化成亚晶粒和位错胞,第二相纳米粒子(M_(23)C_6)分布更弥散均匀;经随后的退火处理,发生了回复和部分再结晶,位错密度有所降低,形成大量尺寸仅几百纳米的等轴亚晶粒.ECAP变形后材料的屈服强度有很大提高(提高至1400 MPa),但延伸率和静力韧度均大幅度下降(分别降至7.3%和100 MJ/m^3);随后的退火处理可恢复其塑性(15.4%),其强度(1044 MPa)和静力韧度(181.6 MJ/m^3)均较初始态(922 MPa,160.7 MJ/m^3)高.The microstructures and mechanical properties of 1Crl6Co5Ni2MoWVNbN martensite heat-resistant steel subjected to equal channel angular pressing （ECAP） for one pass and subse- quent heat treatment were investigated. It was found that most of the martensite lathes had been broken into sub-grain and dislocation cell, and the second phase nano-particles （M23C6） distributed more uniformly after ECAP deformation. By annealing at 680℃ for 2 h, the dislocation density decreased and more amount of equiaxed subgrains with size of several hundred of nanometers formed, while the recovery and recrystallization occured. The yield strength of the ECAPed sample increased significantly （1400 MPa）, but its elongation and static toughness decreased a lot （7.3% and 100 M J/m^3）. After subsequent annealing treatment, both the strength and static toughness of the steel can be in- creased simultaneously （1044 MPa and 181.6 M J/m^3） in comparison with those of initial state.

关 键 词：耐热钢 等径角挤压变形 强度 塑性 静力韧度 

分 类 号：TG142.7[一般工业技术—材料科学与工程]