论文部分内容阅读
近来的研究表明了利用超声波衰减特性分析材料韧性的可能性。然而实际上所有这些研究仅涉及由子材料显微组织的较大变化而引起韧性改变的情形。但当Cr－Mo类钢发生回火脆性时，其韧性将下降而显微组织及抗拉强度不变。因此通常认为很难利用超声波衰减特性来测定因火脆性。本文通过提高超声波频率（达50MHz）来提高探测灵敏度，同时通过实验阐明了超声波衰减特性与回火脆性间的关系。
Recent research shows the possibility of using the ultrasonic attenuation characteristics to analyze the toughness of materials. However, virtually all of these studies have dealt only with the case of changes in toughness caused by large changes in the microstructure of the daughter material. However, when Cr-Mo steels temper brittleness, its toughness will decline and the microstructure and tensile strength unchanged. Therefore, it is generally considered difficult to use ultrasonic attenuation characteristics to determine the fire brittleness. In this paper, we improve the detection sensitivity by increasing the ultrasonic frequency (up to 50MHz). At the same time, the relationship between the ultrasonic attenuation characteristics and the temper brittleness is clarified through experiments.