摘要
针对铜矿湿磨工况下,半自磨机衬板顶端提升条早期断裂的失效行为进行了研究。采用X射线衍射仪(XRD)、光学显微镜(OM)、扫描电镜(SEM)及显微硬度计等分析了衬板提升条和底端处材料的相组成和组织形貌特征,讨论了上述两处材料的磨损机理和裂纹的萌生、扩展行为。结果表明:衬板的冲击磨损机理为疲劳剥落和显微切削,其中顶端提升条处疲劳剥落和显微切削都较明显,而底端则以显微切削磨损为主。衬板使用过程中,顶端提升条长期受到较大的冲击磨损作用,亚表层发生形变而硬化。受形变和夹杂物共同影响,裂纹在形变层内夹杂物周围萌生,随后向基体内部扩展,最终导致衬板断裂。提高衬板用钢熔炼质量,减少衬板夹杂物,并在保证衬板高硬韧性前提下,进一步提高衬板用钢的韧性,将是提高半自磨机衬板使用寿命的必要条件和主要路径。
In view of the wet grinding condition of copper ore,the failure behavior of early fracture at the top lift of the semi-autogenous mill liner was studied.X-ray diffractometry(XRD),optical microscopy(OM),scanning electron microscopy(SEM)and microhardness tester were used to analyze the phase composition and the microstructure of the top lifting strip and the bottom of the liner.The wear mechanism and crack initiation and propagation behavior of the top lifting strip and the bottom of the liner are discussed.The results show that the impact wear mechanism of the liner is fatigue spalling and micro-cutting.The fatigue spalling and microcutting at the top lifting strip of the liner are obvious,and the bottom of the liner is mainly micro-cutting wear.During the use of the liner,the top lifting strip of the liner has been subjected to large impact wear for a long time,and the subsurface layer has produced deformation and work hardening.Affected by the deformation and the inclusions together,microcracks initiate around the inclusions in the deformation layer and then propagate into the matrix,eventually leading to the premature rupture of the liner.To improve the melting quality of lining steel,reduce the inclusions of lining steel,and further improve the toughness of lining steel on the premise of ensuring the high hardness and toughness of lining steel will be the necessary conditions and main paths to improve the service life of lining steel of semi autogenous mill.
作者
陈佳侠
张会友
刁晓刚
李杰
李卫
CHEN Jia-xia;ZHANG Hui-you;DIAO Xiao-gang;LI Jie;LI Wei(Institute of Advanced Wear&Corrosion Resistant and Functional Materials,Jinan University,Guangzhou 510632,Guangdong,China;Qianxi ADI Mechanical Casting Co.,Ltd.,Tangshan 064300,Hebei,China;CITIC Heavy Industries Co.,Ltd.,Luoyang 471003,Henan,China;National Joint Engineering Research Center of High Performance Metal Wear Resistant Materials Technology,Jinan University,Guangzhou 510632,Guangdong,China)
出处
《铸造》
CAS
北大核心
2020年第5期443-448,共6页
Foundry
基金
国家重点研发计划项目(2017YFB0305100)
广东省科技计划项目(2015A040404023,2014B090907005,2017B090903005,2017A090905027,2017B010136115)
广州市科技计划项目(201806040006)。
关键词
半自磨机
衬板
钢
冲击磨料磨损
亚表层
semi-autogenous mill
liner
steel
impact abrasive wear
subsurface
