声发射技术在氧化膜破裂监测中的应用

APPLICATION OF ACOUSTIC EMISSION TECHNIQUE TO MONITORING CRACKING AND SPALLING OF OXIDE SCALES

在高温腐蚀领域，声发射技术是一种最有效且具有极高灵敏度的监测氧化膜破裂的技术．通过分析声发射计数，可以判断氧化膜首次发生破裂的时间及最后破裂的程度．如对声发射频谱进行分析，则可以判别氧化膜内发生塑性变形、开裂及剥落的过程．利用声发射技术还可以测量氧化膜／合金界面处预存物理缺陷大小及分布．此外，将声发射技术与其它技术结合，可建立全新的分析测试系统．综述了声发射技术用于监测氧化膜破裂的原理和方法，以及多种性能测试方面的应用与新发展．

Acoustic emission (AE) has been known for many years as a remote monitoring technique, which can be used to record acoustic waves generated by the sudden release of strain energy during plastic deformation or cracking.In high temperature corrosion field, In-situ detecting cracking and spalling of the oxide scale by AE is remarkably effective. And AE technique may be used in conjunction with other techniques, such as electric thermal microbalance,free bending method for stress measurement,four point bending,high temperature tensile and so on. In this paper, The application and new development of AE is reviewed.