軟鋼用イルメナイト型アーク熔接棒の統計的研究(第2報)

Abstract

Authors analysed on the Statistics of the tensile test value(tensile strength, yield point, yield ratio, elongation and reduction of area) of ilmenite type arc welding electrodes (4 and 5 mm diameters) at the Railway Technical Research Institute, JNR., during 1950-1953 in accordance with JIS G3524 (similar to AWS standard).The results are summarized :1) Distribution types of population of mechanical properties of two diameters were considered as normal. (Table 1, Fig. 2)2) For the mechanical properties of two diameters, minimum, maximum value, distribution range and estimated values of mean and standard deviation were analysed. (Table 2, Fig. 3)3) There were very significant mean differences in the values of tensile strength, yield point and reduction of area between two diametens. The values were higher in the 4 mm than in the 5 mm. (Table 3)4) As to the variance in the tensile strength between the two diameters, the 4 mm was larger than 5 mm. (Table 4)5) Test electrodes mostly gave standard value of D4301 (JIS G3524). Very few did not conform to standard values of tensile strength yield point, but 10% (4mm), and 5% (5mm) fell short of. elongation standard. (Table 5).