复杂应力状态下高温高强度铝合金LD8热疲劳特性的研究  

STUDY OF THERMAL FATIGUE PROPERTIES FOR LD8 ALUMINIUM ALLOY UNDER MULTIAXIAL STRESS STATES

作　　者：张文孝[1] 郭成璧[1] 黄宏发 梁莎莉[1] 倪华 

机构地区：[1]大连理工大学

出　　处：《机械强度》1996年第3期68-71,共4页Journal of Mechanical Strength

基　　金：国家自然科学基金

摘　　要：利用带缺口试件进行了同相和异相热疲劳试验，并借助轴对称热疲劳力学行为的有限元数值分析程序，计算和分析了缺口处的复杂应力和应变，探讨用当量应变范围和当量塑性应变能密度评价热疲劳寿命的可能性。结果表明，在一定加载范围内，当量应变范围和当量塑性应变能密度都可以作为评价复杂应力状态下热疲劳寿命的有效力学参量，而且不受试件形状和尺寸的影响。The in-phase and out-of-phase thermal fatigue were experimentally studied with the circumferentially notched LDS aluminium alloy specimen. Meanwhile,the stress-strain response was calculated at the notch rootby means of the program which simulated the mechanics behaviour of thermal fatigue. The thermal fatigue liveswere evaluated by the methods of equivalent strain range and equivalent plastic strain energy density. The resultsshowed that equivalent strain range and equivalent plastic strain energy density a can all be as the valid mechanicsparameters for predicting thermal fatigue lives within the given loading range. The thermal fatigue lives did not affect by the shapes and sizes of notched specimens.

关 键 词：热疲劳 疲劳寿命 应变范围 

分 类 号：O346.2[理学—固体力学]