Fatigue life and fatigue crack propagation tests have been performed on microsized Ni-P amorphous alloy specimens to investigate the fatigue properties of this material. The material used was a Ni-11.5 wt%P amorphous thin film. The specimens tested were cantilever-beam-type specimen with dimensions of 30 × 12 × 50 μm3 prepared by focused ion beam machining. Notches with a depth of 3 μm were introduced in some specimens. The entire set of fatigue tests was performed using a newly developed fatigue testing machine in air at room temperature under a constant load ratio of 0.1. The fatigue life curve was obtained for unnotched specimens, and the fatigue strength of the specimen was determined to be approximately one-third of the static bending strength. Fatigue crack propagation tests were performed using notched specimens. Fine equispaced markings were observed on the fatigue surface. These markings are aligned perpendicular to the crack growth direction, and are considered to be striations. Therefore, even in microsized amorphous alloys the crack is deduced to propagate by cyclic plastic deformation at the crack tip.
|ジャーナル||Japanese Journal of Applied Physics, Part 1: Regular Papers and Short Notes and Review Papers|
|出版ステータス||Published - 1999|
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