摘要
对6 mm厚和8 mm厚两种规格汽车大梁钢WL510以及WL590、WL700产品共4组数据进行含二维单侧容限系数的升降法分析。结果表明,参考以往经验数据的二维升降法结果的相对偏差比常规的一维升降法有大幅下降。部分情况下,二维升降法结果相对偏差仅为一维方法的1/5。另外,当试验样本量过小时,即使使用二维升降法,试验结果偏差仍较大。因此,即便使用二维升降法也得保证基本的试验样本量。从实测结果来看,该方法不但给出了很好的方差估计量,解决了传统升降法对方差估计误差较大的问题,与传统的只能利用当前试验数据的升降法相比,其可利用的信息量有了大幅度增加,所以在精度相同的情况下,可以节省大量试件;而在试件数一定的条件下,又能提高预测精度。
The fatigue limit of the automotive frame steel include WL700,WL590 and WL510 are investigated. In order to take the thickness effect into account,two series of WL510 samples with 6 mm and 8 mm thickness respectively are selected. The fatigue strengths are calculated by one and two dimensional up-and-down method under different probability of failure and believe. The result shows that the relative deviation of fatigue strength using one dimensional method is 4 times larger than two dimensional method. In addition,more experienced data brings more accurate result. The relative deviation of fatigue strengths become larger when the the sample quantity is small. The Two dimensional method can save many specimens and testing time under the same accuracy requirement. In the other aspect,it can enhance accuracy of the test result with the same number of specimens compares with the traditional one.
出处
《物理测试》
CAS
2017年第2期7-11,共5页
Physics Examination and Testing
关键词
汽车大梁钢
二维升降法
疲劳极限
相对偏差
automotive frame steel
two dimensional up-and-down method
fatigue limit
relative derivation
