超音波探傷試験による部分溶込み突合せ溶接継手の非破壊的強度評価方法

抄録

Partial penetration butt welded joints are widely used, because they require relatively less weld metal to make a joint. However, the unwelded zone acts like a crack. When the size of crack in material is known, the tensile-strength of the material can be estimated using fracture mechanics. This paper deals with a practical method of estimating the size of crack (the unwelded zone in a partial penetration butt welded joint) using ultrasonic testing. The probe refraction angle and a method of ultrasonic testing are discussed. In addition, the tensile-strength of welded joints are also estimated using fracture mechanics, and are found to be in good agreement with experimental results.