4340钢与40CrNiMo钢的热处理特点  

Heat Treatment Characteristics of 4340 Steel and 40CrNiMo Steel

作　　者：廖庚峰 李丰 胡立嵩 黄家瑞 李彩虹 万谦 LIAO Geng-feng;LI Feng;HU Li-song;HUANG Jia-rui;LI Cai-hong;WAN Qian(Jiangxi Hongdu Aviation Industry Group Co.,Ltd.,Nanchang Jiangxi 330095,China)

机构地区：[1]江西洪都航空工业集团有限责任公司,江西南昌330095

出　　处：《热处理技术与装备》2023年第5期5-9,共5页Heat Treatment Technology and Equipment

摘　　要：4340钢与40CrNiMo钢为相似的两种材料,但4340钢中的Ni、Mo元素含量略高于40CrNiMo钢,不同的合金元素含量使材料具有不同的临界冷却速度,两种材料的热处理性能也有明显的差别。4340钢完全退火硬度为32.0 HRC,40CrNiMo钢完全退火硬度<180 HB;4340钢正火后得到马氏体组织,正火硬度为49.0 HRC,40CrNiMo钢正火硬度为31.0 HRC;两种材料在780~870℃淬火,加热温度对淬火硬度没有影响;在相同淬、回火工艺下,4340钢的硬度略高于40CrNiMo钢。4340 steel and 40CrNiMo steel are similar materials,but the content of Ni and Mo elements in 4340 stel is slightly higher than that of 40CrNiMo steel.Different alloy element contents make the material have different critical cooling rates,and the heat treatment properties of two materials also have obvious differences.The complete annealing hardness of 4340 steel is 32.0 HRC,and the complete annealing hardness of 40CrNiMo steel is less than 180 HB.The 4340 steel can obtain martensitic structure after nor-malizing,and the normalizing hardness is 49.0 HRC,while the normalizing hardness of 40CrNiMo steel is 31.0 HRC.The two materials are quenched at 780 to 870℃,and the heating temperature has no effect on the quenching hardness.Under the same quenching and tempering process,the hardness of 4340 steel is slightly higher than that of 40CrNiMo steel.

关 键 词：4340钢 40CRNIMO钢 热处理 硬度 金相组织 

分 类 号：TG161[金属学及工艺—热处理]