High speed wear testing of an abradable coating
High speed wear testing of an abradable coating
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DOI：
10.1016/j.wear.2012.07.009
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发表时间：
2012-07
期刊：
影响因子：
5
通讯作者：
J. Stringer;M. Marshall
中科院分区：
文献类型：
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作者：
J. Stringer;M. Marshall
研制了高速耐磨涂层磨损试验装置。冲击速度在100 ~ 200ms−1之间，侵入速率在3.4 ~ 2000μms−1之间。使用叶片的图像分析、磨损的频闪成像和叶片的扫描电镜对磨损过程进行了进一步的表征。研究发现，侵入率对磨损机制的影响要大得多，在高侵入率的测试中几乎没有磨损或粘附，而在低侵入率的测试中则有明显的粘附和磨损。发现的磨损模式与航空发动机压气机机壳中可磨损涂层的磨损模式一致。结果表明，质量和长度变化的总体测量不足以表征测试过程中遇到的磨损过程的性质，通过叶片的图像分析可以找到更准确的表征。该分析与叶片尖端的SEM图像一起表明，在同一测试过程中同时发生了磨损和粘附；这是由算术表面粗糙度和平均叶片长度的变化来表征的。积聚的频闪成像显示，在低侵入率下，粘附物质的积聚在侵入过程中并不均匀发生，在某些点上积聚的速度大于侵入的速度。这表明，可磨损材料的粘附是由于从可磨损涂层中拔出完整的相，而不是传统的切割机制。
A high speed test rig has been made for analysis of the wear of abradable coatings. Impact velocities between 100 and 200ms−1and incursion rates between 3.4 and 2000μms−1have been used. Further characterisation of the wear process has been performed using image analysis of the blade, stroboscopic imaging of the abrasion and SEM of the blade. It was found that incursion rate had a far greater influence on the wear mechanism, with tests at high incursion rates showing little wear or adhesion, whereas tests at low incursion rates showing significant adhesion and wear. The wear patterns found were consistent with those found in abradable coatings in aero-engine compressor casings. It was shown that bulk measurements of mass and length change were inadequate in characterising the nature of the wear processes encountered during the test, with more accurate characterisation found by image analysis of the blade. This analysis, together with SEM pictures of the blade tip, showed that both wear and adhesion occurred during the same test; this was characterised by the arithmetic surface roughness and change in average blade length. Stroboscopic imaging of the build-up showed that at low incursion rates the build-up of adhered material does not occur uniformly during the incursion, with the rate of build-up being greater than the incursion rate at points. This suggests that the adhesion of abradable material is due to plucking out of complete phases from the abradable coating, rather than a conventional cutting mechanism.