| In the industrial field, the wear and corrosion, especially in high temperature wear and corrosion of circulating fluidized bed boilers'4'burst to the power system and other industries is a huge loss. In recent years, people try various methods to solve this problem, thermal spraying technology to become the most popular pipeline protection technology.Based on the analysis of circulating fluidized bed boiler operating conditions and failure mechanism of heating surface in the case, select the Fe/Cr composite materials for the study, obtain high-performance coatings by electric arc spraying. To facilitate the comparison, select the Ni60 and AT20 two classic coating for comparison tests. Using electron microscopy, scanning electron microscopy (SEM),energy dispersive spectrometry (EDS) and other methods to study the three coating's microstructure, adhesion strength, hardness, thermal shock resistance, hot corrosion, wear and other performance tests. This article also gives special consideration to coating's thermal conductivity on the circulating fluidized bed boiler thermal efficiency, thermal conductivity of three kinds of coatings were tested with the current recognized most advanced laser method.The results showed that:Coatings compact wonderful. They show excellent mechanic properties, with high adhesive strength and micro-hardness, their thermal shocking resistance is also good. Of the three kinds coating, ceramic coating showed the best performance, metal ceramic coating the second,alloy coating weaker, some mechanical properties of Fe/Cr composite coating are close to the AT20 ceramic coating. In the thermal conductivity test results, the worst is ceramic coating and the thermal conductivity of composite coatings is very good. In summary, Fe/Cr composite coating showed a good overall performance, and also indicates that the direction of development of the boiler protective coating material in some extent.
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