Silicon nitride ceramics with its high strength, wear resistance, chemical stability and other advantages can be applied to stationary blades in turbines and metal-based silicon nitride ceramic friction materials. The key to its application is to avoid the defects formed during the preparation. With a long propagation distance and a high susceptibility to interference on a propagation path, Lamb wave can identify the defects in silicon nitride ceramic stationary blades and metal-based silicon nitride ceramic friction materials. In this paper, the lamb wave dispersion curves for silicon nitride ceramic turbine blades and metal-based silicon nitride ceramic friction materials are plotted based on the theory of bisection, and the choices of lamb wave modes and frequency thickness products for their lfaws detecting are given. The most preferable should be the wave with high energy, good waveform and less proneness to mode conversion. It’s expected to provide theoretical basis for the practice of detecting defects in silicon nitride ceramic turbine blades and metal-based silicon nitride ceramic materials.%氮化硅陶瓷以其高强度、耐磨损及高化学稳定性等优越性能被应用于燃气轮机涡轮的静叶片和金属基氮化硅陶瓷摩擦材料中。其应用的关键是避免制备过程中形成的缺陷。利用Lamb波具有传播距离远、检测速度快的特点实现氮化硅陶瓷静叶片和金属基氮化硅陶瓷摩擦材料缺陷检测。采用二分法绘制lamb波在燃气轮机氮化硅陶瓷涡轮叶片和金属基氮化硅陶瓷摩擦材料中的频散曲线,并给出了lamb波检测其缺陷时选择的模态和频厚积范围,应该选择能量高、波形好、不易发生模式转换的模态,为实践检测氮化硅陶瓷涡轮叶片和金属基氮化硅陶瓷摩擦材料缺陷提供理论依据。
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