Dissolving Behaviors of WC Particles in the Laser Cladding
Ni60WC35-based alloy composite coatings were fabricated by multimode CO2 laser apparatus on medium-carbon steel substrate. The microstructure and interface shape of the cladding layer were studied through X-Ray diffraction (XRD), optical-microscope (OM), scanning electronic microscope (SEM) and energy spectrometer (EDS), and the forming mechanism of WC particle was also analyzed. The cross-section microhardness of the cladding layer was measured by Vickers hardness tester. The results show that laser scanning speed greatly influence the microstructure of Ni-based WC composite coating, WC particles have transformed in the Ni matrix during the laser cladding. The main microstructure feature is WC hard phase at the edge have transformed into needle phase,needle phase area can be enlarged through decreasing laser scanning speed, and the area of needle clusters structure expanded gradually. When the molten pool temperature rises to 1250℃,the decomposition of the reaction of WC(2WC→W2C+C) occurs,and the temperature increases continually can accelerate the dissolution of WC particles and elements diffusion.
Zhong Zhang Hongxi Liu Xiaowei Zhang Shengwei Ji Yehua Jiang
Faculty of Materials Science and Engineering, Kunming University of Science and Technology, Kunming, Yunnan 650093, China
国际会议
1st International Conference on Frontiers of Laser Processing(第一届激光加工前沿国际会议 ICFL 2011)
长春
英文
179-180
2011-07-11（万方平台首次上网日期，不代表论文的发表时间）