發(fā)布時間：2018-05-14 04:42

  本文選題：疲勞-蠕變 + 熵增　； 參考：《中國機(jī)械工程》2016年10期

【摘要】：根據(jù)經(jīng)典熱力學(xué)理論,材料疲勞-蠕變交互作用下的損傷過程可視為系統(tǒng)熵增的累積,當(dāng)熵增積累到臨界值時,材料發(fā)生失效斷裂。按此理論,并基于連續(xù)損傷力學(xué)和能量守恒定律,以系統(tǒng)熵增的變化來描述材料損傷,建立了一種疲勞-蠕變交互作用的損傷模型。為驗(yàn)證該模型,進(jìn)行了540℃和520℃環(huán)境下1.25Cr-0.5Mo鋼應(yīng)力控制的梯形波加載試驗(yàn),以材料的殘余應(yīng)變反映熵增積累,選取殘余應(yīng)變的變化作為損傷變量,用上述損傷模型進(jìn)行了材料疲勞-蠕變交互作用的損傷演化描述,結(jié)果表明實(shí)測損傷點(diǎn)數(shù)據(jù)與該模型的損傷演化規(guī)律符合較好。
[Abstract]:According to the classical thermodynamic theory, the damage process under the interaction of fatigue and creep can be regarded as the accumulation of entropy in the system. When the entropy accumulation reaches the critical value, the failure fracture of the material occurs. According to this theory, and based on the law of continuous damage mechanics and energy conservation, the damage of materials is described by the change of entropy increase of system, and a damage model of fatigue creep interaction is established. In order to verify the model, the stress controlled trapezoidal wave loading tests of 1.25Cr-0.5Mo steel at 540 鈩，

本文編號：1886401