Al_2O_3薄片拉伸切口强度及其概率分布的研究

ON NOTCH TENSILE STRENGTH AND ITS PROBABILITY DISTRIBUTION OF THIN ALUMINA SPECIMEN

对Ａｌ２Ｏ３薄片进行了拉伸实验研究，实验采用了金属粘接过渡与铰链式拉伸夹具．结果表明Ａｌ２Ｏ３薄片的拉伸断裂强度与切口强度遵从正态分布、对数正态分布与Ｗｅｉｂｕｌ分布．实验还给出切口强度分布参数与拉伸断裂强度分布参数之间的关系式．利用该关系式和光滑试件测定的断裂强度及其概率分布，可对具有给定应力集中系数的陶瓷构件的断裂强度及概率分布进行预测，为构件的安全可靠性评估提供依据，并节约人力、物力与实验经费．

Tensile tests of notched thin alumina specimen adhered to a piece of thin metal were performed by using hinged fixtures. Results showed that the tensile strength and notch tensile strength followed normal distribution, logarithmic normal distribution and Weibull distribution. The relationship expressions between the characteristic parameters of probability distribution of notch strength and those of tensile strength are given in this paper. In order to find a basis of reliability evaluation of notched components of ceramics of a given stress concentration factor, one can use the values of the tensile strength and its probability distribution measured on smooth specimens to solve these expressions and thus predict the notch strength of ceramics and its probability distribution, which can reduce time and fare consumption.