摘要
金属疲劳是一个能量耗散过程 ,其中主要的能量耗散形式包括内耗热和储能。储能是材料缺陷数量、分布及损伤状态的宏观体现 ,它需要借助于材料的热发射间接地获得。本文利用细小热敏电阻测量了 4 0 Cr Ni Mo A,80 90和 TC4三种材料在低周疲劳过程中的热发射规律 ,试验中观察到了温度涨落现象 ,发现热发射与材料的热传导系数、疲劳寿命和加载频率有关 。
Fatigue of metals is an energy dissipation process. The main energy dissipation includes the internal friction and the stored energy. The stored energy is the macroscopic indication of the amount and distribution of micro-defects and the damage state. It can be obtained indirectly recurring to the heat response. The rules of thermal emission during LCF of 40CrNiMoA, 8090 Al-Li and TC4 were measured utilizing a kind of small thermistance. The temperature fluctuation was observed during the experiments. It was found that the thermal emission was dependent on the heat conductivity of materials, the fatigue life and frequency. A formula of the maximum temperature was given.
出处
《机械科学与技术》
CSCD
北大核心
2003年第5期799-801,共3页
Mechanical Science and Technology for Aerospace Engineering
关键词
金属
低周疲劳
能量耗散
热发射
温度测量
Low cycle fatigue(LCF)
Thermal dissipation
Temperature measurement
