Abstract:Two welding wires including Cr3C2-Ni-Al and WC-Ni-Al were produced by pressureless sintering in vacuum. When the welding wires were welded on the surface of carbon steel by the manual gas-tungsten arc welding, carbide particles reinforced Ni3Al base composites were formed by the physical heat of arc and Ni-Al exothermic reaction. XRD showed that Ni reacted with Al to form Ni3Al in both wires during welding. Microstructure and hardness tests showed that carbides distributed in matrix and strengthened matrix differently, which was mainly attributed to their different physical characters (such as density, melting point). WC appeared as large particles and segregated on welding interfaces, and hence the strengthening effect was small. However, Cr3C2 was decomposed during welding to form the dispersed Cr7C3 with stripe shape, which strengthened the matrix significantly. The room and high temperature hardness of Cr7C3/ Ni3Al composite was much higher than that of Stellite alloys. Cr7C3/Ni3Al composite is attractive as potential candidate for high-temperature surface wear-resistant material.
李尚平, 骆合力, 冯涤, 曹栩, 张喜娥. 碳化物特性对Ni3Al基表面强化复合材料组织与性能的影响[J]. 材料工程, 2004, 0(11): 53-56.
LI Shang-ping, LUO He-li, FENG Di, CAO Xu, ZHANG Xi-e. Influence of Carbides Characters on Microstructure and Properties of Ni3Al Base Surface-strengthening Composites. Journal of Materials Engineering, 2004, 0(11): 53-56.
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