316L表面制备Ni-AI系金属间化合物层的耐铅铋腐蚀性能

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Lead-bismuth corrosion resistance of Ni-Al intermetallic compound layer prepared on 316L surface

ZHU Qiang，YAO Shusheng，ZHAO Xinyi，LI Hongliang，ZHU Zhaojian （Jiangsu University，Zhenjiang 212O13，Jiangsu，China）

Abstract：A layer coating of Ni6O aloy powder was deposited on the surface of 316L stainless steel by laser cladding technology，and pure Al coating was prepared on the surface of Ni6O alloy coating by thermal spraying technology.Then，Ni-Al intermetallic compound was generated between Ni6O alloy coating and pure Al coating by 620C×5 h high temperature difusion test. Finally，the specimens prepared with Ni6O ally and Ni-Al intermetallic compound coating were placed in liquid lead-bismuth alloy for 400°×500h to conduct corrosion test.SEM and XRD were used to test morphology，phase composition and element distribution of surface and section of intermetalliccompound coating before and after corrosion，andcorrosion resistance of Ni6O ally coating and intermetallic compound coating in liquid lead-bismuth at 400‰ was analyzed. The test results showed that after high temperature difusion test，a layer of Ni-Al intermetallic compound composed of Ni3Al and NiAl was generated on the surface of specimens. After 400∘C liquid lead-bismuth alloy corrosion test， surface corrosion of Ni6O ally coating was more serious，a large number of metal elements on the surface were oxidized and dissolved，and discontinuous metal oxidesand corosion pits were formedon the surface of specimens.Ni-Al intermetallic compound coating was oxidized and became a stable metal oxidecoating，which could efectively prevent Pb，Bi，Oand other elements from penetrating into substrate and improve corrosion resistance of 316L to liquidlead-bismuth.

Key words： laser cladding； high temperature diffsion; intermetalic compound; lead-bismuth corrosion

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铅冷快堆是第四代核反应堆的6种（钠冷快堆、气冷快堆、铅冷快堆、超临界水堆、超高温堆和熔盐堆）主要堆型之一，具有良好的核废料嬗变和核燃料增殖能力及较高的安全性和经济性，发展和应用前景广阔[1-4]。（剩余7765字）