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工程陶瓷材料可分為結(jié)構(gòu)陶瓷和功能陶瓷兩大類,前者主要利用陶瓷機械性能。材料的力學(xué)性能主要研究材料在外力作用下發(fā)生彈性或塑性形變、材料抵抗形變的能力和材料失效或被 破壞的規(guī)律。陶瓷材料多以離子鍵、共價鍵,或者兩者的混合鍵結(jié)合。
從結(jié)構(gòu)的特點來說, 這類晶體的剛性強,材料總體上硬度高、耐磨損、耐高溫和耐腐蝕,但是脆性大,塑性差,不易進行加工,抗熱震性也較差,強度分散。對這類材料施載時,內(nèi)部或表面的裂紋容易擴展并將引起應(yīng)力集中,使材料發(fā)生突然的災(zāi)難性斷裂。
強度是材料抵抗變形和破壞的能力。根據(jù)加載形式的不同,材料內(nèi)部的應(yīng)力可歸納為三類:拉伸正應(yīng)力,壓縮正應(yīng)力和剪切應(yīng)力。在這些應(yīng)力作用下,材料破壞的強度分為拉伸強度、壓縮強度和剪切強度。另外,根據(jù)外加載荷特征分為彎曲強度,扭曲強度,沖擊強度和疲勞強度。(圖/文tujian.net.cn)
中譯英:
Engineering ceramic materials can be divided into structural and functional ceramics two categories, the former mainly using ceramic mechanical properties. Mechanical properties of materials research materials under external force of elastic or plastic deformation, material to resist deformation capacity and material failure or destruction of. Ceramic material with ionic bond, covalent bond, or a mixture of both bond.
From the structural characteristics, this kind of crystal material on the whole rigidity, high hardness, wear resistance, high temperature resistance and corrosion resistance, but the brittleness, ductility, easy processing, thermal shock resistance is poor, intensity distribution. On this kind of material loading, inside or on the surface of the crack propagation easier and will cause stress concentration, so that a sudden catastrophic fracture of materials.