Development of Optimum Proof Testing Method of Structural Ceramics

结构陶瓷最佳验证测试方法的开发

基本信息

批准号：
01850021
负责人：
ICHIKAWA Masahiro
金额：
$ 4.86万
依托单位：
The University of Electro-Communications
依托单位国家：
日本
项目类别：
Grant-in-Aid for Developmental Scientific Research
财政年份：
1989
资助国家：
日本
起止时间：
1989 至 1991
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-01850021/
关键词：
Fine Ceramics Structural Ceramics Proof Test Reliability 信頼性ファインセミラックス

项目摘要

The aim of this research is to develop the optimum method of proof testing of structural ceramics. The optimum method implies such a method by which the highest probability of surviving proof testing is attained under the condition that S_<fmin>*S_d, where S_<fmin> is the minimum strength after proof testing and S_d is the required strength. The principal results of the research are summarized as follows.1. The optimum proof testing method was first studied for the case of uniform stress distribution. It was found that the optimum testing method is to use the maximum unloading rate available and the test load which satisfies S_<fmin>=S_d under this unloading rate.2. The optimum proof testing method was then studied for the case of non-uniform stress distribution. This case Is Important as real machine components are generally subjected to non-uniformly distributed stresses. It was found that the optimum testing method is to use the maximum unloading rate available and the test load whi … More ch satisfies S_<fmin>=S_d at the point of the maximum stress in the component.3. The influence of the K-V relation on the effect of proof testing was studied by means of computer simulation, where K is the stress intensity factor and V=da/dt is the stable crack growth rate. It was found that when the unloading rate is larger than the critical unloading rate, exterpolation of the first region's K-V relation to the second and third regions does not result in substantial error in calculation of the minimum strength after proof testing and the probability of surviving the proof test.4. A method for estimating the critical unloading rate was proposed, and the usefulness of this method was demonstrated experimentally.5. For application of proof testing to ceramic bearing balls, the statistical properties of the ring crack initiation strength and the final fracture strength under crushing load were clarified experimentally. Furthermore, a probabilistic theory for interpreting the experimental results was proposed.6. Proof testing of Si_3N_4 bearing balls was conducted and importance of unloading rate was demonstrated experimentally. Less

这项研究的目的是开发最佳的结构陶瓷测试方法。最佳方法意味着在S_ <fmin>*S_D的条件下附着的最高验证测试的最高概率，其中S_ <fmin>是证明测试后的最小强度，而S_D是所需的强度。研究的主要结果总结如下1。最佳的证明测试方法首先研究了应力分布的情况。发现最佳测试方法是使用可用的最大卸载率，并在此卸载率下满足S_ <fmin> = S_D的测试负载2。然后研究了最佳的证明测试方法，以实现不均匀应力分布的情况。这种情况很重要，因为实际机器组件通常受到不均匀分布的应力。发现最佳测试方法是使用可用的最大卸载率和测试负载，而……更满意的S_ <fmin> = S_D在组件中最大应力的点3。通过计算机模拟研究了K-V关系对证明测试影响的影响，其中K是应力强度因子，V = DA/DT是稳定的裂纹生长速率。已经发现，当卸载速率大于关键卸载速率时，第一区域的K-V与第二和第三区域的外部序列化并不会在证明测试后的最小强度和证明测试的生存概率上计算最小强度的计算误差。4。提出了一种估计关键卸载率的方法，并通过实验证明了该方法的实用性5。为了将验证测试应用于陶瓷轴承球，通过实验阐明了环形裂纹启动强度和最终断裂强度的统计特性。此外，提出了一种解释实验结果的概率理论。6。进行了SI_3N_4轴承球的证明测试，并通过实验证明了卸载率的重要性。较少的