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阻碍热喷涂技术广泛应用的最大障碍之一就是在喷涂过程中缺乏在线控制方法。热喷涂涂层的优化方法是通过对喷涂参数和喷涂参数一涂层性能相关性的经验性调整。而对于一些固有参数是无法调整的，如双丝电弧喷涂过程中的焰流波动和雾化喷嘴磨损，尽管这些参数对涂层的质量有巨大影响，但出于简化目的通常系统地忽略不计。本文中采用声发射分析法，基于所获得的声信号对不可调节参数的影响进行分析。将声发射感应器同时安装在基体和喷嘴上，使得对喷涂过程中的声信号变化进行简单测定成为可能。当增加电流时，一个降低的声信号被记录下来，从而可对不可控参数、声信号和涂层质量之间的相关性进行分析研究。这项研究将有助于探索喷涂过程中的在线控制方法。“,”One of the greatest obstacles for a wide distribution of thermal spraying techniques is the lack of online control over the spraying process. The thermally sprayed coatings are optimized by an empirical modification of the spraying parameters and the subsequent correlation of these parameters to the obtained coatings. Some intrinsic parameters, such as the fluctuations in twin wire arc spraying and wear in theatomization nozzle, are not adjustable. Even though they have an enormous impact on the obtained coating quality, they are often scientifically neglected for reasons of simplification. In this work, acoustic emission analysis is utilized to study the effect of uncontrollable parameters on acoustic signals. In order to enable an easy determination of the changes in the acoustic signals, the acoustic sensors were mounted on the spraying nozzle as well as on the substrate. At increased current, a lower acoustic emission is recorded. A correlation between uncontrollable parameters, the acoustic signals, and the obtained coating quality was observed. This research contributes to the online control of the spraying process.