等离子熔射皮膜温度过程监控

Process Monitoring of Coating Temperature in Plasma Spraying

提出一种红外测温仪结合机器人熔射路径进行在线温度检测的新方法,实现了对预热、熔射与冷却过程中基体与皮膜温度的在线监控。为保证监控系统的实时性,参考统计学方法采用周期温度均值与标准差等特征信息对温度变化趋势进行表征。结果表明:选取的特征量能够简单、直观地反映温度变化;能够对温度波动和皮膜破坏等现象做出及时响应;能够辅助熔射工艺分析与过程监控、诊断。同时也为等离子熔射过程控制提供了一种新途径。

A novel method for measuring substrate and coating temperatures is presented. It is realized by an infrared pyrometer combined with specific robot spraying trajectories. With this method, substrate and coating temperatures can be continually detected and recorded during preheating, spraying and cooling stages on the basis of the pyrometer reading. Two major factors, periodic average temperature and standard deviation were adopted to evaluate the temperature variation and its fluctuation based on the statistical method for the real-time performance of a process monitoring system. Results show that these two factors were successful in describing temperature variation, coating damage and other phenomena in time during experimental processing. Our method can be applied to the processing analysis and in-situ process diagnosis and monitoring, and is also suitable for process control of plasma spray.