Effect of addition of nitrogen on the microstructure and properties of cold-forged-roll steels  

作　　者：WU Qiong 

机构地区：[1]Research Institute,Baoshan Iron&Steel Co.,Ltd.,Shanghai 201999,China

出　　处：《Baosteel Technical Research》2020年第1期19-27,共9页宝钢技术研究（英文版）

摘　　要：The heat-treatment characteristics,mechanical properties,and wear behavior of four cold-forged-roll steels were studied and their microstructural characteristics were analyzed using transmission electron microscopy(TEM),scanning electron microscopy(SEM),X-ray diffractometer(XRD),and an oxygen-nitrogen analyzer.The results show that the introduction of nitrogen facilitates improvement in the mechanical properties of cold-forged rolls.A solid-solution strengthening effect is obtained by interstitial nitrogen,and the hardenability of rolls can be improved as well.A significant effect on grain-size refinement is obtained by highly thermally stable fine M(C,N)carbonitrides,which pin the grain boundaries during austenitization and block the growth of austenitic grains.Compared to conventional roll steels,the optimum quenching temperature of steel with added nitrogen can be increased by 20-30℃ Therefore,the hardening temperature range is expanded,which is beneficial to the heattreatment process.Furthermore,high-hardness carbonitrides can improve the wear performance.

关 键 词：CARBONITRIDE cold-forged ROLL microstructure mechanical property wear behavior 

分 类 号：TG142.1[一般工业技术—材料科学与工程]