50AZ弹链淬火硬度不均原因分析及改进措施  

Cause analysis and improvement measures of uneven quenching hardness of 50AZ cartridge belt

作　　者：戴扭乾 刘涛[1] 付清霞 邱香花[1] DAI Niuqian;LIU Tao;FU Qingxia;QIU Xianghua(Xinyu Iron and Steel Group Co.,Ltd.,Xinyu 338001,Jiangxi,China)

机构地区：[1]新余钢铁集团有限公司,江西新余338001

出　　处：《江西冶金》2021年第5期61-65,共5页Jiangxi Metallurgy

摘　　要：主要对50AZ弹链淬火硬度不均、局部硬度偏低的样品取样,进行了成分、金相、显微维氏硬度、电镜等分析。结果表明:50AZ弹链淬火硬度低的主要原因是弹链原料表面存在脱碳现象,且局部位置脱碳层较深。在同一淬火热处理条件下,表面脱碳处的奥氏体化不完全,淬火临界冷却速度增大,脱碳处获得的是以屈氏体为主、少量马氏体和未溶碳化物的混合组织,导致表面硬度低。通过严格控制热轧板坯加热时间与加热温度、退火炉炉内氧含量与密封性等措施,能有效避免弹链原料表面产生严重脱碳现象。In this paper,the composition,metallography,micro Vickers hardness and electron microscope of the samples with uneven hardness and low local hardness were analyzed.The results show that the main reason for the low quenching hardness of 50AZ cartridge belt is that there is decarburization on the surface of cartridge belt raw material,and the decarburization layer is deep in some parts.Under the same quenching heat treatment condition,the austenization on the decarburized surface is incomplete,the critical cooling rate increases,and the mixed structure of Troostite,a small amount of martensite and undissolved carbide is obtained at the decarburized surface,which leads to the low surface hardness.By strictly controlling the heating time and temperature of hot rolled slab,oxygen content and sealing property in annealing furnace,serious decarburization on the surface of cartridge belt raw material can be effectively prevented.

关 键 词：50AZ 弹链 脱碳 硬度 

分 类 号：TG157[金属学及工艺—热处理]