摘要
对于结构陶瓷的工程应用来说,抗冲击性最为重要。本文的主要目的是:(1)研究陶瓷材料在高速载荷下的冲击强度和测试方法;(2)从理论上找出冲击时间与冲击靶材料特性之间的关系及临界破坏参数的确定。文中推导了梁试件受冲击的冲击响应,最大冲击力和应力的表达式,并对结构陶瓷的动态破坏机理进行了分析和讨论,认为脆性的本质是材料的裂纹扩展速率。对干脆性材料,从可靠性来考虑并不是强度越高越好。对两种陶瓷材料进行了不同冲击速度的冲击弯曲强度测试,给出了冲击速度与冲击强度间关系的理论和实验曲线以及最大冲击力与系统固有频率的关系。
The problems being dealt with in this study include the calculation method ofimpact srength for beam specimen,the relationship between maximum impact force and load-ing speed as well as load-stress relation in dynamic case,and the definition of critical impactparameter.In this paper,the dynamic fracture mechanism of ceramics was analysed and dis-cussed.It was considered that the degree of brittleness depends on cracking rate of materilas.Insome cases,the reliability of brittle ceramics is not in proportion to strength.Experiments of im-pact bending strength at different impact speed were performed on two kinds of ceramics.Thetheoretical and experimental curves about the dependance of strength on impact speed werepersented.
关键词
结构陶瓷
冲击
强度
陶瓷
structural ceramics
impact strength
critical evaluation
inertia force
