論文
TiNi 形状記憶合金ワイヤーの疲労特性に与える超音波ショットピーニングの影響
2019 年 2019 巻 64 号 p. 33-37
詳細
2019 年 2019 巻 64 号 p. 33-37
The influence of ultrasonic shot peening (USP) on the rotating-bending fatigue life and the initiation point of the fatigue crack of shape memory alloy (SMA) wire were investigated. The effect of the compressive residual stress on the fatigue life of USP-treated SMA wire was discussed. The results obtained are summarized as follows. (1) The effect of the USP to the fatigue life of SMA is large in the small strain and slight in the large strain. (2) In the case of the USP-treated wire with coverage of 2000% and 4000%, the compressive residual stress cannot be measured around the surface. The structure on the surface may become the amorphous. (3) In the initiation point of the fatigue crack, the larger the coverage, the larger the ratio of the appearance of fatigue crack in the specimen surface is.
