AE法によるMIM材の疲労損傷評価に関する研究: 第1報，カオス解析と周波数解析の適用

摘要

Metal injection molding (MIM) is a suitable production technique for the mass production of the products of the complicated shape. The MIM materials produced by the technique have the properties that are excellent in the static mechanical properties such as the tensile strength. However, the studies on the dynamic properties such as the fatigue strength that is important for the design of the reliable structural sintered steels are not enough. Our aim is to evaluate the fatigue damage of MIM materials with AE method. In this study, the detected AE signals during the fatigue testing of the material were analyzed with weight mean frequency distribution, chaos time series analysis, et al. As the result, the possibility that the damage will be evaluated by the parameters that were proposed in this study was shown.%粉末冶金法は比較的高強度で複雑な製品形状を経済的に生産することができるので，自動車用部品をはじめとするさまざまな分野で使用されている．しかし，き裂の発生起点と進展経路に影響を及ぼす気孔が数多く存在するために，引張強さや疲労強度などの機械的性質の低下は避けられない． このようなことから，従来の1/10以下の平均粒径の金属粉末を有機系バインダで加熱混練したのちに成形し，脱バインダと焼結を行う金属粉末射出成形（Metal Injection Molding：MIM）法が提案された．