光学精密工程2011，Vol.19Issue(7)：1515-1523,9.DOI:10.3788/OPE.20111907.1515
不锈钢表面多道激光熔覆Ni基涂层的组织与性能
Microstructures and properties of multiple-pass laser cladding Ni-based coatings on stainless steel surface
摘要
Abstract
In order to improve the surface hardness and corrosion resistance of stainless steel, singlepass and multi-pass lap laser cladding coatings of Ni25WC35 alloy powders were fabricated on a 1Crl8Ni9Ti substrate by a 6 kW transverse-flow CO2 laser. The coatings were examined and tested for chemical compositions, microstructure features, phase structures, microhardness, corrosion behaviors and metallographies by the X-ray Diffraction (XRD), Scanning Electronic Microscopy (SEM), X-ray Energy Dispersive Analysis (EDAX), microhardness tester, electrochemistry workstation and optical microscopy (OM), respectively. The results show that some new harden phases are formed in the coating which consists of (Fe, Ni) solid solution and some compounds such as WC,W2C, CrNiFeC, FeW3C, Ni2Si, Fe3Ni3B, and these harden phases improve the hardness and corrosion resistance of the substrate effectively. OM observation displays that the microstructure of clad coating is homogeneous, compactness and forms a good metallurgical bonding layer with the substrate. Micro-hardness measurement exhibits that the surface hardness of treated sample is twice as large as that of substrate, and the highest hardness lies in the second pass cladding zone center of a double-pass coating sample and reaches 650HV. The electrochemical corrosion test in 5.0％ NaC1 saturated solution indicates that the maximum self-corrosion potential (Ecorr) of clad coating sample changes from 630.90 mV to positive direction, and the lowest corrosion current density (Icorr) changes from 2.21 μA ·cm-2 to 0.55 μA· cm-2 and decreases by 75.11％. Compared with the substrate, the corrosion resistance of laser cladding sample has been improved significantly, and the single pass clad-ding sample shows the best corrosion behavior.关键词
激光熔覆/多道涂层/不诱钢/显微硬度/腐蚀性能Key words
laser cladding/ multi-pass lap coating/ stainless steel/ microhardness/ corrosion behavior分类
矿业与冶金引用本文复制引用
刘洪喜,曾维华,张晓伟,王传琦,蒋业华..不锈钢表面多道激光熔覆Ni基涂层的组织与性能[J].光学精密工程,2011,19(7):1515-1523,9.基金项目
国家自然科学基金资助项目(No.50671045) （No.50671045）
云南省自然科学基金资助项目(No.2008ZC021 M) （No.2008ZC021 M）
昆明理工大学分析侧试基金资助项目(2009-022) （2009-022）
