Ultrasonic Fatigue of Tisub40/subZrsub10/subCusub34/subPdsub14/subSnsub2/subGlassy Alloy

摘要

In this work, ultrasonic fatigue behavior of the Ti40Zr10Cu34Pd14Sn2 glassy alloy was investigated at 20 kHz at a stress ratio of R = -1. The number of cycles to failure in the S-N curve obtained in this work did not decrease again even after 107 - 108 cycles unlike previous findings for some steels. The fatigue endurance limit and the fatigue rate were σW = 762 MPa and σW/σB = 0.37, respectively. Fish-eye type inertial crack initiation, reported in many papers on giga-cycle fatigue testing, was not observed. A tendency for the fatigue strength of the Ti40Zr10Cu34Pd14Sn2 glassy alloy specimens to be divided into two groups was observed, that is, specimens with a short fatigue lifetime (6 cycles) with distinct cast defects as crack initiation sites and the other specimens with a long fatigue lifetime (>106 cycles). This may have been caused by accidental nucleation of micro-defects such as impurities, voids and precipitates in the glassy rod specimens during the casting.