论文部分内容阅读
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。
Impact resistance is paramount for engineering applications of structural ceramics. The main purpose of this paper is: (1) to study the impact strength and test method of ceramic materials under high-speed load; (2) to theoretically find out the relationship between the impact time and impact target material properties and determine the critical failure parameters. In this paper, the impact response, maximum impact force and stress expression of the beam specimens are deduced. The dynamic failure mechanism of the structural ceramics is analyzed and discussed. The brittleness is considered as the crack growth rate. For dry and brittle materials, reliability is not the highest strength. The impact strength and flexural strength of two kinds of ceramic materials with different impact velocities were tested. The theoretical and experimental curves of the relationship between impact velocity and impact strength, and the relationship between the maximum impact force and the natural frequency of the system were given.