AT_（30）Z金属陶瓷材料的冲蚀机理及其影响因素

Solid particle effects on erosion mechanisms of AT_(30)Z cermets

本文用ＳＥＭ研究了一系列ＺｒＯ２增韧ＡＴ３０金属陶瓷（也称ＡＴ３０Ｚ），在不同冲蚀速率及冲蚀角组合条件下的冲蚀形貌及流失机制；结果表明：随垂直入射动能增大，材料表面相继出现应力疲劳→晶粒剥离→应变疲劳及高角铲削的冲蚀机制的过渡交换，各机制的法向速度门槛值Ｖａ、Ｖｂ和Ｖｃ与靶材的断裂韧性Ｋｃ等靶材性质有关，而与冲速率及冲蚀角无关．本文建立了冲蚀速度座标系，以综合分析冲蚀速率及冲蚀角对冲蚀的影响，分析结果与ＳＥＭ观察吻合．

n this paper the eroded Surface morphology of a series of zirconia toughende AT30Z cermets samples by SEM at different erosive situations was investigated. The test resultsshowed that: with increase of normal component of impact energy En, erosion mechnnismstransition were observed correspondently: stress fatigue(low En ), radial cracking and graindispartching (medium En ), strain fatigue and shoveling(high En) ;Threshold normal components of impact energy of the above -- mentioned mechanisms (Ea,Eb and Ec ) were relatedwith fracture toughness Kc, hardness ration Hp/Ht, however appeared little relation withimpart velocity and angle. A zoned Vn -- Vt rectangular coordinates system was plotted tocover influence of impingement velocity V and angle a on erosion mechanism, A comprehensive erosion rate equation was derived for AT30Z ceramic series by means of elastic-- plasticmechanics and fracture mechanics analysis which could explain the ε -- α curves and ε -- Vcurves from the ceramics well.