工業用純チタンの疲労き裂発生過程と切欠き感度

概要

論文の詳細を見る
Push-pull fatigue tests with zero mean stress were carried out on commercial purity titanium sheet specimens, in order to investigate the crack initiation characteristics and notch sensitivity. Special attention was given to the starting point of fatigue cracking at the root of a notch with various sharpness, and fatigue processes were observed successively. The followings were obtained; (1) The crack initiation process is the one in which the definite regions whose dimensions are closely related to the grain size, turn gradually into free surfaces as a whole by the repetitions of slop. (2) No non-propagating crack is initiated even for a specimen with a notch root radius of 0.1 mm. (3) The material is notch insensitive for blunt notches, however, appreciably sensitive for sharp ones due to absence of non-propagating cracks, compared to 7:3 brass and mild steels.
1984-05-25