Failure mechanism and acoustic emission signal characteristics of coatings under the condition of impact indentation

High Temperature Materials and Processes

Ming Liu¹  Guo-Lu Li²  Tian-Shun Dong²  Ran Wang² 

[1] National Key Laboratory for Remanufacturing, Academy of Armored Forces Engineering, Beijing 100072, China;School of Materials Science and Engineering, Hebei University of Technology, Tian jin 300130, China;

关键词: coating;    bonding strength;    impact indentation method;    acoustic emission;   

DOI  :  10.1515/htmp-2019-0007

来源: DOAJ

【 摘 要 】

In this work, the substrate, NiCr coating, Al2O3 coating with NiCr undercoating and Al2O3 coating were tested by an impact indentation device equipped with an acoustic emission (AE) detection equipment. The surface morphology, dimension, cross-sectional image, 3D topography of indention and bonding strength of coatings were analyzed. The failure mechanism and AE signal characteristics of the coatings under impact were studied. The results demonstrate that the failure mode of NiCr coating was dominated by interface cracking, and that of Al2O3 coating is fracture and accompanied by a small amount of interface cracking, while Al2O3 coating with NiCr undercoating possesses common characteristics of the first two. The energy counting and wave voltage of AE signal were more sensitive to the bonding strength of coating in the impact process, which can be used to characterize the bonding strength of coating.

【 授权许可】

Unknown