采用强流脉冲离子束(HIPIB)辐照方式获得了特性(孔隙率、微裂纹及致密度)不同的Cr2O3陶瓷涂层。利用超声反射系数谱相邻极小值频率间隔Δf与涂层厚度d之间的关系Δf=c2/2d求得了涂层声速c2。对应于原始及辐照1次和5次涂层试样,超声声速分别为2 002,2 099和2 197 m/s,声速提高表明涂层弹性性能增强。SEM结果表明,涂层经辐照后孔隙及裂纹减少,涂层变得致密,同时其表面显微硬度提高。超声试验结果与理论分析一致,利用声速能够对HIPIB改性的Cr2O3涂层特性进行超声表征。

High-intensity pulsed ion beam (HIPIB) irradiation was performed on the plasma sprayed Cr2O3 coatings with the thickness of 50 μm and different properties of coatings have been obtained. The velocity was deduced based on the frequency interval between the minima of the reflection coefficient. The results have shown that the velocity increased from 2 002 m/s for as-sprayed coating to 2 099 and 2 197 m/s 1 and 5-shot irradiated coatings. With increasing the shot number,the enlarged splats reformed by serious splats remelting and sufficient cavities sealing induced more uniform and compact structure. The observations of SEM and microhardness agree with that of the ultrasonic analysis. The research indicated that the velocity could be used to characterize the properties of the plasma sprayed coatings irradiated by HIPIB.