A study of methodological nature demonstrates the efficiency of a probation test allowing for the intrinsic character of a rheological constitutive law to be assessed. Such a law is considered here for semicrystalline polymers exhibiting necking and for large deformation. In the framework of a law of behavior of \(( \dot{\sigma },\sigma , \dot{\varepsilon },\varepsilon )\), tensile experiments conducted at an imposed constant strain rate \(\dot{\varepsilon }_{0}\) bring true stress responses, from which the constitutive (material) parameters can be identified from model-based metrology concepts. The same experiment repeated at various strain rates gives an access to the dependence of the nonelastic parameters on the strain rate. Then the intrinsic law is tested severely by considering a new set of experiments carried out for constant displacement rates of the grips. In that case the specimens show local strain rates that evolve strongly during the test (by a factor of 5–10). The parameter identification process requires the introduction of the exact realized input strain and strain-rate command into the model. Accounting for strain rate dependency additionally requires the knowledge of the preliminary identified strain rate dependence of the nonelastic constitutive parameters for good predictions of the experimental response directly. This is what is proven here. The conclusion speaks in favor of a possible upgrade of international standards for the mechanical characterization of polymers based on constant strain-rate tensile tests and properly applied model-based metrology.

方法学性质的研究表明，缓刑测试的效率允许评估流变本构法的内在特征。对于呈现颈缩和大变形的半结晶聚合物，这里考虑这样的定律。在\（（\ dot {\ sigma}，\ sigma，\ dot {\ varepsilon}，\ varepsilon）\）的行为定律的框架内，以施加的恒定应变率\（\ dot {\缬草} _ {0} \）带来真正的应力响应，可以从基于模型的计量概念中识别出本构（材料）参数。在不同的应变率下重复进行的同一实验可以使非弹性参数与应变率相关。然后，通过考虑为夹具的恒定位移率执行的一组新实验，对内在规律进行严格测试。在这种情况下，样品显示出局部应变率，该应变率在测试过程中会剧烈变化（5-10倍）。参数识别过程要求将精确实现的输入应变和应变率命令引入模型。考虑到应变率依赖性，还需要了解非弹性本构参数的初步确定的应变率依赖性，以便直接对实验响应进行良好的预测。这就是证明。该结论表明，基于恒定应变速率拉伸试验和适当应用的基于模型的计量学，可能对国际标准的聚合物的机械性能进行升级。