長時間クリープ破断データの整理法についての考察

抄録

It is required that the creep rupture strength of steels for high temperature services will be estimated upon many data for production of one given kind of steels by statistical procedure. When the stress-rupture time diagram is used, there are two methods of estimating 10⁵h creep rupture strength, one by finding the regression curve of rupture time for stress and its confidence limit, and the other by calculating the mean value and confidence limit from the strength of each material. In the present report discussion is made of the validity of the two above mentioned methods based upon the long time data for production of six charges of high strength boiler tubes. Of the two methods in question it is found that the latter has proved preferable in the majority of cases.