※ 引述《Andretti (Rookie)》之铭言： : 大家好! : 请问固体(Soild),小至碳酸钠粉末之类的, : 可以检测固体的黏度(Viscosity)单位[cP]吗? : 还是只有流体有黏度,固体没有黏度呢? : 问题: : 1.固体有没有黏度呢? : 2.一般来说(95%以上的状况而言), : 固体(Solid)是无法测黏度而且黏度系数(cP)也无法知道是多少吗? : 3.理论上来说(5以下的状况而言), : 固体(Solid)是可以测黏度而且可以黏度系数(cP)也知道是黏度多少吗? : 谢谢大家! 我再wiki上看到，但其实wiki的东西也不能完全尽信啦 Can solids have a viscosity? If on the basis that all solids flow to a small extent in response to shear stress then yes, substances know as Amorphous solids, such as glass, may be considered to have viscosity. This has led some to the view that solids are simply liquids with a very high viscosity, typically greater than 1012 Pa‧s. This position is often adopted by supporters of the widely held misconception that glass flow can be observed in old buildings. This distortion is more likely the result of glass making process rather than the viscosity of glass. However, others argue that solids are, in general, elastic for small stresses while fluids are not. Even if solids flow at higher stresses, they are characterized by their low-stress behavior. Viscosity may be an appropriate characteristic for solids in a plastic regime. The situation becomes somewhat confused as the term viscosity is sometimes used for solid materials, for example Maxwell materials, to describe the relationship between stress and the rate of change of strain, rather than rate of shear. These distinctions may be largely resolved by considering the constitutive equations of the material in question, which take into account both its viscous and elastic behaviors. Materials for which both their viscosity and their elasticity are important in a particular range of deformation and deformation rate are called viscoelastic. In geology, earth materials that exhibit viscous deformation at least three times greater than their elastic deformation are sometimes called rheids. One example of solids flowing which has been observed since 1930 is the Pitch drop experiment 作者以glass为例也指出may be considered to have viscosity 有些物质随温度昇高时，固液两态并没有明显界限。对於这种情况，作者用dynamical viscosity 大於多少来界定，上面的例子指出dynamical viscosity大於10^12次方Pa．s时，定为固态。 所以我觉得固体也是有cp的。 --

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