金属材料内の超電波の減衰（V）白銑と焼鈍可鍜鋳鉄

抄録

Measurements of attennstion of ultrasonic waves in white and annealed cast irons were carried out in the frequency range from 2 to 25 megacycles per second. The attenuations were measured for various stages of graphitization of the cast iron: Specimens were annealed for the purpose of graphitization several times successively and the mesurements were made at each stages of these heat treatments. It has been found that (1) the general feature of attenuation curves is monotonous increase with frequency and (2) with the advance of the degree of graphitization the attenuations increase in the range of higher frequencies.