Application of Time-Temperature-Stress Superposition Principle to Nonlinear Creep of Poly(methyl methacrylate)
Application of Time-Temperature-Stress Superposition Principle to Nonlinear Creep of Poly(methyl methacrylate)
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DOI：
10.4028/www.scientific.net/kem.340-341.1091
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发表时间：
2007-06
期刊：
影响因子：
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通讯作者：
W. Luo;C. Wang;R. Zhao
中科院分区：
文献类型：
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作者：
W. Luo;C. Wang;R. Zhao
在14 ℃ ~ 26 ℃和6 MPa ~ 32 MPa的不同温度和应力水平下，测量了商品级聚甲基丙烯酸甲酯的单轴拉伸蠕变4000 s。所得蠕变柔量曲线偏离彼此的应力超过一个临界值，随温度变化，表明非线性粘弹性行为。采用时间-温度-应力叠加原理（TTSSP），从较高应力和温度下的短期试验中获得了一条时间尺度间隔较长的光滑主柔度曲线。结果表明，主曲线涵盖了超过290天的时间，这是近3.9个十年的时间比测试持续时间。此外，它被验证的时间-温度偏移因子取决于应力，在该偏移被施加，并且时间-应力偏移因子取决于参考温度。
The uniaxial tensile creep of a commercial grade Poly(methyl methacrylate) was measured for 4000 seconds under various temperatures and stress levels ranging from 14 oC to 26 oC and 6 MPa to 32 MPa. The resultant creep compliance curves depart from each other for stresses beyond a critical value which varies with temperature, indicating nonlinear viscoelastic behavior. The time-temperature-stress superposition principle (TTSSP) was used to construct a smooth master compliance curve with a much longer time-scale interval from the short-term tests at higher stresses and temperatures. It is shown that the master curve covers a period of over 290 days, which is nearly 3.9 decades longer than the test duration. Moreover, it is verified that the time-temperature shift factors are dependent on stresses at which the shifts are applied, and that the time-stress shift factors are dependent on reference temperatures.