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研究了Ｎｉ－２０Ｃｒ合金在ＨＣｌ＋Ｈ２气氛中１０２３Ｋ和１２２３Ｋ下的高温氯化腐蚀行为。热力学计算表明，Ｎｉ－２０Ｃｒ合金氯化的相平衡图中存在两个不同的区域，在较低ＰＨＣｌ／ＰＨ２和较高温度区，主要的氯化产物是气相ＣｒＣｌ２（ｇ）；在较高ＰＨＣｌ／ＰＨ２和较低温度区，将形成凝聚相ＣｒＣｌ２（ｃ）。热重测定发现，在ＣｒＣｌ２（ｇ）稳定区合金的氯化动力学表现为速率随时间变化的质量损失行为，由气相扩散引起的线性过程和固相扩散引起的抛物线过程串联控制；在ＣｒＣｌ２（ｃ）稳定区，其氯化动力学表现为质量增加。氯化后样品表面形貌证实了热力学分析与动力学测定结果。

High temperature chlorination behavior of Ni-20Cr alloy in a (HCl+H2) gas mixture was studied.Thermodynamic calculations predicted that there are two different regimes of stable chlorination productsdepending on gas ration of PHcl/PH2 and temperature.In the regime of lower ratio of PHcl/PH2 andhigher temperature,the only important chlorination product is volatile CrCl2(g), and in the regime of higherratio of PHcl/PH2 and loWer temperature,the condensed phase CrCl2(c)becomes thermodyllamicallystable. The chlorination kinetics study was carried out in the two different regimes by TGA measurements.A time dependent mass loss rate was observed in first experimental regime. Further analysis of tile kineticdata indicated that the chlorination rate limiting process is a linear gas phase transport in series witha parabolic process of the substrate diffosion of Cr. In the second experimental regime,the growth ofcondensed product leads to m~ gain behavior. The surfaCe of the alloy after chlorination in the firstregime showed pitting morphology. A surfaCe scale was visible for the alloy after chlorination in the secondregime. These obserVations are consistent with the expectation of the thermodynamic analysis and theresults of kinetic measurements.