25MnV钢矿用圆环链热浸镀铝及其力学性能的研究  

Study on Hot Dip Aluminum of 25MnV Steel Round Link Chains for Mining and Its Mechanical Properties

作　　者：许亿 李光[1,2] 陈玉玺 王同会 李德胜 王巍智 夏原 XU Yi;LI Guang;CHEN Yuxi;WANG Tonghui;LI Desheng;WANG Weizhi;XIA Yuan(Institute of Mechanics,Chinese Academy of Sciences,Beijing 100190,China;University of Chinese Academy of Sciences,Beijing 100049,China;China Juli Group,Baoding 072550,China;North China University of Science and Technology,Tangshan 063210,China)

机构地区：[1]中国科学院力学研究所,北京100190 [2]中国科学院大学,北京100049 [3]中国巨力集团,河北保定072550 [4]华北理工大学,河北唐山063210

出　　处：《热加工工艺》2023年第23期119-122,127,共5页Hot Working Technology

基　　金：河北省省级科技计划专项(16241026H)。

摘　　要：采用扩散热浸镀铝对25MnV钢矿用圆环链进行处理,对热浸镀铝层的显微组织、显微硬度以及圆环链的拉伸性能和破断性能进行研究。结果表明:热浸镀铝后表面为铝层和Fe-Al合金层,合金层主要相为Fe_(2)Al_(5)和FeAl_(3),合金层内高硬度区域比例较高。经850℃、4 h的扩散处理后,铝层全部转变为合金层,且分为外扩散层与内扩散层,外扩散层主要相为FeAl,内扩散层主要相为Fe_(3)Al,合金层内高硬度区比例明显降低,且内扩散层的显微硬度小于基体。扩散后由于高温抗氧化性的Fe-Al合金层的形成,降低了淬火和回火过程中表面氧化程度,从而提高了其抗拉强度和屈服强度。由于Fe-Al合金层的硬度较高,使得扩散热浸镀铝拉伸件的伸长率和收缩率有所降低。与链条原件相比,热浸镀铝和扩散对破断强度变化不大,而两者的伸长率出现了下降,但两者性能均满足国标对C级别圆环链要求。Hot-dip aluminizing and diffusion annealing were carried out on 25MnV steel round link chains for mining.The microstructure,microhardness,stretching properties and breaking properties of the coatings were studied.The results show that the coatings consist of aluminum layer and Fe-Al alloy layer.The major phase of the alloy layer is Fe_(2)Al_(5) and FeAl_(3),and the area of high hardness of the alloy is larger.After diffusion annealing treatment at 850℃ for 4 h,the aluminum layer transforms into alloy layer completely.The alloy layer can be divided into an outer diffusion layer and inner diffusion layer.The major of the outer diffusion layer is FeAl and the inner diffusion layer is mainly composed of Fe_(3)Al,and the region of high hardness in the alloy layer is smaller.The microhardness of the inner diffusion layer is lower than the substrate.After diffusion,due to the Fe-Al alloy layer with high temperature oxidation resistance,the oxidation of tension piece in the process of quenching and tempering reduces and then the tensile strength and yield strength improve.The elongation and shrinkage of the diffused aluminized tensile parts reduce result from high hardness of Fe-Al alloy layer.Compared with the non-treatment chain,the breaking load of the aluminized chain and the diffused aluminized chain show little change,but the elongation both obviously decreases.In addition,their properties both meet the Chinese standard of C-level ring chain.

关 键 词：25Mn钢矿用圆环链 热镀铝 热扩散 拉伸 破断 

分 类 号：TG174.443[金属学及工艺—金属表面处理]