Abstract
Plain fatigue properties of commercially available Zr-based bulk amorphous alloy (7.6Ni–12.3Cu–3.5Al–76.6Zr in mass%) in a phosphate buffered saline (PBS(−)) were studied and compared with those in air. Fatigue tests were carried out under load control using a sinusoidal waveform at a stress ratio of 0.1 at a frequency of 20 Hz in air or 2 Hz in PBS(−). There was no difference between S–N curve of plain fatigue in air and that in PBS(−). Fatigue limits were detected in both environments and their fatigue strengths at ten million cycles were approximately 150 MPa. The ratio of the fatigue strength to the ultimate tensile strength was 0.12. Fatigue fracture surface in PBS(−) was the same as that in air. Plain fatigue crack initiated at inner defects or impurity particles near the specimen surface except for the specimen in which the cracks were initiated at the square corner of the parallel gauge section.
