再制造零件通常采用表面工程等先进技术进行加工，使其性能恢复，甚至超过新产品。简要介绍了目前再制造零件在线监测的发展现状。针对再制造零件喷涂涂层在服役过程中易出现的缺陷，概述了用于涂层失效检测的红外检测技术、声发射检测技术、超声无损检测检测技术，并综述了国内目前应用于涂层零件在接触疲劳过程中在线监测技术，而这些技术均是监测涂层零件失效后的信息，不能实现对涂层失效过程的在线监测。基于此提出了一种思路，考虑将智能材料嵌入涂层与基体之间，通过采集智能元素的信号来监测涂层零件的服役情况，探讨了进一步研究的方向和解决问题的思路。

Advanced surface engineering technology is often used to fabricate remanufacturing components to restore their properties close to or even better than those of new products. This paper briefly introduces the development of on-line monitoring of remanufacturing components. For the defects generated during the service process of plasma sprayed coatings, this paper summarizes the infrared detection technique, acoustic emission testing technique, and ultrasonic nondestructive testing technique which are utilized to detect the failure of coatings. In addition, on-line monitoring techniques which are applied to coatings during contact fatigue process are also overviewed. However, the above techniques only can detect the defects of failed coating components, and can not realize on-line detection of failure process. To this problem, this paper proposes a new method to detect the failure process of coating components through collecting the signals of smart materials which are embedded between the coating and substrate. Further research plan and the method to solve problems are also discussed.