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目的 获得电火花沉积质量较好的Ni201 修复层. 方法 运用电火花沉积技术,采用DHD-6000型电火花沉积设备在Q235 钢表面制备Ni201 修复改性层,利用电子扫描显微镜( SEM )、能谱仪( EDS)、X射线衍射( XRD)等检测方法,研究修复层与基体结合界面的微观结构、元素分布、相组成以及修复层表面残余应力. 结果 Ni201修复层组织均匀致密,基体与修复层之间发生元素扩散;修复层结合界面处主要由Fe10. 8Ni、γ( Fe,Ni)固溶体、CoFe15. 7及Fe相组成;Ni201修复层表面残余应力随能量输出幅度的增加而增大,在40%与45%能量输出条件下,残余应力分别为-38. 1,-81. 6 MPa,残余应力较小. 结论 Q235钢基体与Ni201修复层元素相互扩散,基体与修复层之间形成了冶金结合,Ni201修复层为冶金结合层. 再制造修复设备工艺参数选择是决定修复层质量的关键因素,能量输出幅度为40%的修复层质量优于能量输出幅度为45%.

Objective To obtain a Ni201 restoration layer with a better quality by electro-spark deposition. Methods Using e-lectro-spark deposition technology, Ni201 restoration layer was prepared on Q235 steel surface with the DHD-6000 type electro-spark deposition equipment, the microstructure, chemical elements distribution, phase composition of the bonding interface be-tween the restoration layer and the substrate, and residual stress on the surface of the restoration layer were investigated by means of scanning electron microscopy, energy dispersive spectrometer, and X-ray diffraction. Results The microstructure of Ni201 resto-ration layer was uniform and dense, and there was interdiffusion of elements between the restoration layer and the substrate, the main phases of the restoration layer bonding interface were composed of Fe10. 8Ni, γ(Fe,Ni), CoFe15. 7 and Fe, the residual stress on the surface of the restoration layer increased with the increase of power output amplitude, the residual stress was -38. 1 MPa and -81. 6 MPa under the conditions of 40% and 45% energy output, respectively, and the value of residual stress was low. Conclusion The interdiffusion of elements between the Ni201 restoration layer and the Q235 steel substrate indicated formation of metallurgical bonding between the substrate and the restoration layer, and the Ni201 restoration layer was a metallurgical bonding layer. The key factor for the quality of the restoration layer was determined by the process parameters selection of remanufacturing repair equipment, and the quality of the restoration layer prepared with an energy output amplitude of 40% was better than that pre-pared with an energy output amplitude of 45%.