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本文由不可逆过程热力学第一、二定律理解和计算位错应力激活速率,所得位错速率υ中有三个新的方面:(1)反映相互作用的活度系数γ,γ~≠;(2)与激活自由能ΔZ_0~≠平列的“激活内耗”,Δ~≠;和(3)可能把位错动力学和塑性学增量理论连接起来的“激活畸变增量”,Δe_(mn)~≠与畸变功: υ_0——位错体积; S_(jk,ejk)——偏应力、应变; 本文的理论方法与结果可为深入研究提供参考。

Thermodynamical functions of metal-dislocation system are defined in phy-sico-chemical space of states by taking P=(1/3)σ_(kk) in connection with plastic in-compressibility. Irreversible shear deformation of this system is treated by the-rmodynamical laws of irreversible processes. In a way equivalent to the introduction of entropy production from theclassical second law for irreversible processes, the free energy change ΔZ_(T.P) isexpressed in terms of dissipations Δ' and Δ_Z, ΔZ_(T.P)= -A'_(iR)-Δ_Z when distor-sion work A'_(iR) is done by the system, and ΔZ_(T.R)= A'_(iR)-Δ', when work is doneto the system by applied deviational stress field, S_(jk). In a way parallel to the derivation of Nernst equation for reversible cells,the above ΔZ_(T.P) expressions, together with reaction isotherm, ΔZ_(T.P)=ΔZ_0~≠+kTln (γ~≠x~≠/γx), give the concentration x~≠ of activated dislocations, and simple kin-etic arguments lead to the rate of movement v, of dislocations under applieddeviational stress field S_(jk):wherein Δ' and Δz are taken to be equal for the case of symmetrical barrier,Δ'=Δ_z=Δ~≠ which is the monotonous internal friction of irreversible stress acti-vation; Δe_(mn)~≠ is the deviational increment of activation, and v_0, the volume ofeach dislocation. Other results are given in the Chinese text.