热处理工艺对12Cr1MoVG厚壁无缝钢管表面硬度的影响  

Effect by Heat Treatment on Surface Hardness of 12Cr1MoVG Heavy-wall Seamless Steel Tube

作　　者：肖功业[1] 秦利波[1] 何彪[1] 赵庆权[1] 

机构地区：[1]天津钢管集团股份有限公司,天津300301

出　　处：《钢管》2015年第3期20-24,共5页Steel Pipe

摘　　要：分析了12CrlMoVG厚壁无缝钢管组织分布状态与硬度的关系；通过测定其CCT曲线，确定出Ф219mmx45mm规格12CrlMoVG厚壁无缝钢管的最佳热处理工艺：淬火970℃×60min、水淬20s，回火750℃×150min。生产结果表明：通过控制淬火时间，可减少铁素体的析出量，避免马氏体组织的大量析出，从而实现产品硬度的控制；新热处理工艺实现了12CrlMoVG厚壁无缝钢管硬度在161～182HB内的稳定控制，表面硬度合格率达100％，且其各项机械性能指标均满足标准要求。Investigated in the article is the relationship between the micro-structural distribution status of the 12CrlMoVG heavy-wall seamless steel tube and its surface hardness. Based on the measured CCT curve of it, the optimum heat treatment process for the Ф219 minx45 mm 12CrlMoVG heavy-wall tube is determined, involving such critical parameters as furnace quenching： temperature 970 ℃, time 60 minutes; water quenching： time 20 s; tem- pering： temperature 750 ℃, time 150 minutes. The actual operation result of the said heat treatment process demons- trates that with proper control of the quenching time, the ferrite segregation amount can be reduced, so as to prevent remarkable segregation of the martensitic structure, and thus get satisfactory control of the product hardness. The newly-set heat treatment process ensures that the hardness range of the 12CrlMoVG heavy-wall tube is consistently kept as 161-182 HB, and the surface hardness qualification rate thereof is up to 100%, while all the other mechani- cal property data are in compliance with relevant requirements under the applicable product standard.

关 键 词：无缝钢管 12CR1MOVG 厚壁钢管 金相组织 表面硬度 热处理工艺 淬火 回火 

分 类 号：TG161[金属学及工艺—热处理] TG142[金属学及工艺—金属学]