等离子熔射皮膜破坏温度场诊断

Diagnosis of temperature of field of coating damage in plasma spray

应用红外热像仪获取等离子熔射过程中基体与皮膜发生破坏时的温度场,对比分析皮膜破坏发生区域。然后从通过破坏区域的直线上的温度变化曲线,深入分析该区域的温度波动。实验结果表明:皮膜破坏一般发生在预热后基体温度较高区域和温度较高区域向临近温度偏低区域过渡部位;温度曲线中,皮膜破坏区域对应的温度极大值要高于临近区域平均温度30℃～50℃或者更高。实验结果为等离子熔射过程中皮膜温度监控确定了皮膜破坏预警信息和核心目标监控区域。

In this paper,temperature fields of substrates and coatings taken by thermal imager when the coating damage happened were comparatively studied to find the occurrence area of damage,and then the temperature curve through the damage area was obtained for the further discussion of temperature fluctuation in this area.Experimental results demonstrate that coating damages always happen in the higher temperature area and the transition area from the higher temperature to the lower in the substrate because of high thermal stress,and the temperature difference between the peak in the scope of coating damage and the mean of the relevant circumambience regions is beyond 30 ℃-50 ℃ or even higher in the temperature versus time curve.Experimental results provide the process monitoring of coating temperature the prewarning of coating damage and the focusing scope in plasma spray.