很多結構元件在變動負荷及溫度情況下工作，由於溫度梯度、材料非等向性及結構幾何因素造成結構元件存在拘束限制及力平衡限制條件。
先依Valanis之內涵時間黏塑性理論、Lee之「決定『內涵時間黏塑性理論』中材料函數之一有系統方法」及Sehitoglu對1070鋼在各溫度下循環應力-應變實驗遲滯曲線，決定1070鋼在各溫度下之材料參數、材料常數，並建立材料參數及材料常數對溫度之關係式。再利用內涵時間黏塑性增量模式，進行循環應力-應變分析，以確認增量式及相關材料參數對溫度關係之正確性，結果與實驗數據相當符合。
最後建立增量式內涵時間熱循環黏塑性模式，利用Sehitoglu等人之實驗為對象，分別對1070鋼在 (1)部份拘束熱循環負荷實驗、 (2)完全拘束熱循環負荷實驗及 (3)過度拘束熱循環負荷實驗下的材料行為進行模擬，由計算結果證明本模式對1070鋼部份拘束熱循環應力-應變整體行為具有理想的描述能力；但對完全及過度拘束熱循環應力範圍之值有偏大的預估，且熱循環平均應力也有偏向壓應力之現象，此結果會影響熱循環壽命之預估。往後如對本理論引入應變率敏感度函數 及潛變效應，可望獲得較小的計算應力增量，並使其疊積量能符合實驗值。

Many structural members in service experience fluctuating loads and temperatures. The constraint and the equilibrium equations exist in structural components due to temperature gradient, material anisotropy, and geometry effects.
Material parameters and constants in the theory of Endochronic cyclic viscoplasticity of 1070 steel alloy are determined from Sehitoglu’s isothermally experimental hysteresis respone at 293K, 573K, 673K and 873K. The functional relationship of material parameters and constants with temperature are then taken. The computation results using the incremental form of the theory are in very well agreement with the experimental data.
The incremental theory is then tested by a 1070 steel alloy two-bar structure under thermal cycles with different constraint conditions. The constraint types are (a) partial constraint, (b) total constraint, and (c) over constraint. Through the computational stress-strain responses, the theory has descriptive ability in the partially constraint condition. However, under both total and over constraint conditions, the stress ranges calculated are greater than those of experimental data, and the cyclic mean stress has phenomenon of having intention to the compressive stress. These will influence the prediction of thermal-cycle life. Later introducing the strain rate sensitivity material function and joining the creep effect, the theory may make smaller stress increments and their accumulations may agree with the experimental data.

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