【摘要】 本试验对合铌基体钢65Cr4W3Mo2VNb（简称65Nb）进行了循环相变强韧化处理。试验结果表明，该钢经1080～1120℃快速加热二次循环淬火，540℃回火，其强韧性进一步提高。其中1080℃二次循环淬火C型缺口试样冲击值由常规处理83J／cm2提高到136J／cm2（提高65％），烧度由8．6mm提高到9．9mm（提高15％），抗弯强度由4490MPa提高到4678MPa、若在循环淬火之前增加一次高温固溶540℃弥散析出，使钢中的碳化物超细化，强度还可提高10％，达到4890MPa。本研究成果对生产中制订65Nb钢的复合热处理及返修工艺有指导意义。更多还原

【Abstract】 篢his Paper deals with the investigation of the cyclical phase transformation strength-toughening treatment of the niobium ccntained matrix steel 65Cr4W3Mo2VNb (abbreviated 65Nb). It is denoted that by rapid heating at 1080- 1120℃ with double cyclical quenching and tempered at 540℃,the strength and toughness of the steel can be furtherly raised, "C"type notched impact toughness (ak),deflection (f)and bending stength (the)are significiently increased simultaneously at 1080 ℃ double cyclical quenching,exhibiting an increase of approximate 65%, 15% and 4% respectively as compared with single quench hardening.By adding the high temperature solution treatment and the dispersive precipitation of the carbides at 540℃be fore the cyclical hardening to make the carbides superfine,the strength of the steel can be even increased.This paper has also the guiding meaning for establishing the process of compound heat treatment and repairing process for 65Nb steel.更多还原