正火工艺对含Cu大型球墨铸铁行走轮组织和性能的影响  

Effect of normalizing process on microstructure and properties of large nodular cast iron travel wheel containing Cu

作　　者：肖结良 孙浩 李飞[1] 胡平 解扬 陈旌钢 Xiao Jieliang;Sun Hao;Li Fei;Hu Ping;Xie Yang;Chen Jinggang(Hefei Casting and Forging Factory of Anhui Heli Co.,Ltd.,Hefei Anhui 230601,China)

机构地区：[1]安徽合力股份有限公司合肥铸锻厂,安徽合肥230601

出　　处：《金属热处理》2025年第2期256-259,共4页Heat Treatment of Metals

摘　　要：对一种Cu微合金化球墨铸铁的大型行走轮进行了正火工艺试验,研究了正火温度(850℃和880℃)对行走轮轮缘和轮辐微观组织和力学性能的影响。结果表明,含Cu大型球墨铸铁行走轮在850℃低温正火只能获得部分珠光体,尚有25%~30%(体积分数)的破碎状铁素体,导致轮缘的强度达不到要求。在880℃正火(风机鼓风冷却)+550℃回火后,轮辐和轮缘的力学性能均能满足要求。880℃正火相比850℃正火获得较多珠光体,这是由于正火温度升高,奥氏体中碳含量增加,过冷奥氏体的稳定性增大,C曲线右移,亦即在冷却时易于获得珠光体。对于大型球墨铸铁行走轮,选择较高的正火温度如880℃为佳。A normalizing process experiment was conducted on a large travel wheel made of nodular cast iron containing 0.460%Cu,and the effect of normalizing temperature(850℃and 880℃)on the microstructure and mechanical properties of the travel wheel flange and spoke was studied.The results show that the large nodular cast iron travel wheel containing Cu can only obtain partial pearlite after low-temperature normalizing at 850℃,and there is still 25%to 30%(volume fraction)fragmented ferrite,resulting in the strength of the wheel flange not meeting the requirements.After normalizing at 880℃(fan blown cooling)and tempering at 550℃,the mechanical properties of the flange and spoke can meet the requirements.More pearlite forms when normalized at 880℃than that at 850℃.This is because as the normalizing temperature increases,the carbon content in austenite increases,the stability of undercooled austenite increases,and the C-curves shift to the right,making it easier to obtain pearlite during cooling.For the tested large nodular cast iron travel wheels,a higher normalizing temperature such as 880℃is preferred.

关 键 词：行走轮 球墨铸铁 正火工艺 力学性能 微合金化 

分 类 号：TG164.2[金属学及工艺—热处理]