磨辊辊齿等离子弧Ni-Cr共渗研究

Study on Preparation of Surface Ni-Cr Permeation Layer of Milling Roller Teeth by Plasma Arc

运用高能等离子体弧束在常压下快速扫描均匀涂覆镍铬合金渗剂的磨辊辊齿表面,对辊齿进行多元共渗和自激冷淬火复合强化处理,并对辊齿表面硬化层组织结构和性能进行了研究。结果表明,合金元素扩渗层达40μm,整个硬化层深度为200～270μm;合金化层硬度约为729.5HV,淬硬层硬度为815.2HV。辊齿表层硬度提高,硬度梯度分布合理,且齿有较好的韧性,可有效提高辊齿的耐磨性,延长辊齿使用寿命。

By scanning the milling roller-teeth surface coated with the uniform Ni-Cr alloy permeation layer through the high energy plasma arc at ordinary pressure, the multicomponent permeation and quenching harden were carried out. The microstructure and composition of harden layer was investigated and analysed. The results show that, the depth of permeation layer is more than 40 μm and the depth of totalharden layer is 200～270 μm. The microhardness of multicomponent permeation layer is 729.5 HV and the microhardness of quenched layer is 815.2 HV. The harden layer of teeth improves, and hardness gradient distributes properly. The application of the craft in milling roller teeth highly improves the surface toughness, stiffiness and wear resistance, and prolongs the life-span of milling roller.