Matching between Base Metal and Weld Metal on viewpoint of Reliability on Welded Joints on Static Tensile Strength

Abstract

Mechanical properties of steels and welding rods are usually random variables, so mechanical properties of welded joints which are made using those materials are also them. In this report, it is pointed out that the reliability of welded joints on static tensile strength must be considered in discussion about matching between base metal and weld metal. The average tensile strength σ^W_u of weld metal is dependent upon the reliability of welded joints, the form of frequency histogram of their strength and the parameter r which decides the lowest required strength of weld metal. A few calculations about the average tensile strength σ^W_u of weld metal were done and the effects of the reliability, r-value and frequency distributions on strength were considered. On these calculation results, the problem of matching was discussed in relation to the reliability.