新型Cr-Ni-Mo和Cr-Ni-Co堆焊合金空蚀性能

Cavitation Erosion Resistance of Novel Cr-Ni-Mo and Cr-Ni-Co Overlaying Alloys

摘要:

采用钨极氩弧焊（TIG）将新型Cr-Ni-Mo和Cr-Ni-Co合金堆焊于304不锈钢表面进行空蚀试验，通过失重比较不同合金的抗空蚀性能。采用扫描电镜（SEM）、X射线衍射（XRD）仪和显微硬度计对合金层进行分析。结果表明：Cr-Ni-Mo和Cr-Ni-Co合金的耐空蚀性能均优越于304不锈钢，其中Cr-Ni-Co优于Cr-Ni-Mo；空蚀破坏优先出现在堆焊层的晶界处；Cr-Ni-Co合金在空蚀过程中发生了因奥氏体向马氏体的转变，有利于能量吸收，延缓了空蚀的进行，提高其耐空蚀性能；堆焊合金的抗空蚀能力与合金本身的硬度和加工硬化能力有关。

Abstract:

New type Cr-Ni-Mo and Cr-Ni-Co overlaying alloys were prepared by argon tungsten-arc welding (TIG) on 304 stainless steel, and tested by cavitation vibrating device. The cavitation erosion resistance of alloys was compared through the analysis of mass loss. The alloy layer was analyzed by scanning electron microscopy (SEM), X-ray diffractometer (XRD) and microhardness tester. Results indicate that the cavitation erosion resistance of Cr-Ni-Mo and Cr-Ni-Co overlaying alloys is better than that of 304 stainless steel, and the resistance of Cr-Ni-Co is better than Cr-Ni-Mo. In the process of cavitation the damage is preferred to appear in grain boundary. Phase transformation from austenite to martensite happens in the cavitation process of Cr-Ni-Co alloy, and it is helpful to absorb the energy and delay the process of cavitation erosion, and enhance the cavitation erosion resistance effectively. The cavitation erosion resistance of overlaying alloys is related to hardness and work hardening ability.