本文利用增量式內涵時間對定拉伸應力下循環剪應變衍生之軸向蠕變本構方程式模擬Gao等人對Sn/3.5Ag銲錫材料於定溫298K，定應變率 ，施行剪應變循環 ( )並施加定軸向應力( )所得到軸向蠕變量之數據。核心函數為 ，其中 之值考慮試件測試體積效應。利用 求得之潛變屈服函數 含有三個區域。其中區域III， 為 的線性方程式。假如 之值是由循環塑性剪應變量求得，則Gao等人之軸向蠕變數據皆會落在區域III，導致蠕變量對循環圈數有過大之乘冪關係。因此循環負荷下內涵時間之定義，不適用於定拉伸應力下循環剪應變衍生之軸向蠕變計算。
本文重新定義蠕變下之內涵時間為 ， 及 皆為 之函數，並推導出含定拉伸應力下循環剪應變衍生之軸向蠕變乘冪式，並對Gao等人之實驗數據進行預測，穩態圈數 內之計算結果良好，其中 而 。當 時，因損傷效應的產生，軸向蠕變量會急遽上升，本文以穩態下最大蠕變量為準依蠕變上升率來定義損傷因子 並代入軸向蠕變乘冪式模擬損傷效應，在 、 下，其計算值與實驗數據相當貼合。

In this paper, the incremental form of Endochronic Plasticity for uniaxial ratcheting induced by cyclic shear strain with constant tensile stress was employed to investigate the data of uniaxial ratcheting of Sn/3.5Ag solder at constant temperature provided by Gao et. al., under cyclic shear strain amplitudes ( ) with constant strain rate , and constant tensile stress ( ). To determine the kernel function , the volume size effect of specimen was employed. The creep compliance function converted from has three regions. The 3rd region of is linear in . If the values of were calculated based on cyclic plastic shear strain, then the ratcheting data of Gao et. al., will be in region III. This resulted in a higher dependence of in . Therefore, the definition of intrinsic time is improper to calculate uniaxial ratcheting induced by cyclic shear strain with constant tensile stress.
In this paper, the intrinsic time under ratcheting was proposed in , and are functions of , and resulted in a power form of uniaxial ratcheting induced by cyclic shear strain with constant tensile stress. Under steady response, , , the results predicted were very well as compare with the experimental data. Beyond steady response, is increased very rapidly due to damage. In this paper, damage factor is defined by using the rise of ratcheting base on the difference between real and steady . By using the present Endochronic plasticity with damage, the results can predicted the data of very well.

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