基于涡流法的航空发动机关键部件热障涂层厚度测量试验研究

热障涂层材料可显著提高航空发动机重要部件的耐高温性、耐氧化性、耐磨损性等性能,在实际工程应用中,热障涂层厚度对基体材料的使用性能有重要的影响。采用多频多参数涡流法对热障涂层厚度测量,研制弹压式涡流测厚探头,研究不同测量频率及热障涂层厚度下的涡流测量信号,选取2个最佳激励频率反演热障涂层厚度,为验证多频多参数涡流法的测量精度,利用扫描电镜测量涂层厚度,对比分析两者测量获得的涂层厚度。结果表明:粘接层和陶瓷层的相对误差分别在15%和10%之内,均在测试允许范围,多频多参数涡流法可望实现热障涂层材料厚度的有效测量。

Experimental Study on Thermal Barrier Coating Thickness Measurement of Key Component of Aero-enigine Based on Eddy-current Method

Thermal barrier coating materials can significantly improve the high temperature resistance, oxidation resistance, wear resistance and other properties of key components of aero-engines. In practical engineering applications, the thickness of the thermal barrier coating has important influence on the performance of the base material. The multi-frequency and multi-parameter eddy current method is used to measure the thickness of the thermal barrier coating, and an elastic eddy current thickness probe is developed. The thickness of the thermal barrier coating was retrieved with two optimal excitation frequencies. In order to verify the measurement accuracy of the multi-frequency and multi-parameter eddy current method, the coating thickness was observed using a scanning electron microscope, and the coating thicknesses obtained by the two measurements were compared and analyzed. The results show that the relative errors of the adhesive layer and the ceramic layer are within 15% and 10%, respectively, which are in the industrial allowable range. Therefore, the multi-frequency and multi-parameter eddy current method can effectively measure the thickness of the thermal barrier coating material.