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一、结构疲劳强度概况疲劳强度在机械强度设计中占有重要的位置。据统计,机械零部件断裂事故中,有50～80％是属于疲劳强度不够而引起的。金属的疲劳断裂早为人们所注意。1830年德国Albert用焊接起重链做疲劳试验,到10~5次循环而疲劳断裂。1850年已开始做了梁的弯曲疲劳试验。但是疲劳强度理论用于产品设计上,还是二十世纪初期的事,先首是航空,以后才机械工业。结构疲劳强度是研究整机及零部件在各种类型的变载荷下及不同环境下的疲劳失效机理、断口性态、计算和试验方法、以及安全设计准则等一门学科。正确地应用疲劳理论于强
First, the structure fatigue strength profile Fatigue strength in mechanical strength design occupies an important position. According to statistics, 50-80% of mechanical parts breakage accidents are caused by insufficient fatigue strength. Metal fatigue fracture early attention. In 1830 Germany Albert welded lifting chain fatigue test, to 10 to 5 cycles and fatigue fracture. 1850 Began bending fatigue test beam. However, the theory of fatigue strength is used in product design or in the early twentieth century. The first is aviation and the other is machinery industry. Structural fatigue strength is to study the whole machine and components in various types of variable load and under different environments fatigue failure mechanism, fracture behavior, calculation and test methods, as well as a safety design guidelines and other disciplines. Correct application of fatigue theory in the strong