Determination of viscoelastic properties by nanoindentation

作者：Mencik J^*; Benes L

来源：Journal of Optoelectronics and Advanced Materials, 2008, 10(12): 3288-3291.

• Mechanical properties
• measurement
• indentation
• nanoindentation
• hardness
• viscoelasticity
• elastic modulus

Indenter penetration into viscoelastic materials depends on the load magnitude and history of loading, Hardness is not a constant, but decreases with the time under load. Corrections must be made in the unloading curve used for the determination of contact area and,,instantaneous" elastic modulus. The viscoelastic properties are best characterised by means of rheologic models consisting of springs and dashpots. The constants in these models can be obtained easily from the time course of indenter displacement under constant load, but one must respect also the deformations occuring during the load increase from zero to the nominal load. The paper explains the principle of instrumented indentation, gives the theory and formulae for elastic-plastic and viscoelastic materials, and describes the practical procedure for testing and data evaluation.

• 出版日期2008-12