Heat Treatment by Ultra-sonic Heating : Ultra-sonic Quenching

The principle of heat treatment by ultra-sonic heating lies in using the calorification originated from internal friction in metals caused by ultra-sonic vibration with large amplitude to the materials. Therefore, this heat treatment is a partial one which depends on the vibration mode and also is a kind of thermomechanical one. In this paper, we establish a method of ultra-sonic heating and make clear the properties of quenched material by ultra-sonic heating and make clear the properties of quenched material by ultra-sonic heating. From the results of material tests, it becomes clear that mechanical properties of metal treated by ultra-sonic quenching are by no means inferior to those of metal treated by the conventional quenching (electric furnace), and their hardened microscopic structure is extremely fine. Particularly, from the fatigue tests, interesting results are obtained.