Three-point microbend size effects for pure Ni foils

The three-point microbend tests are performed for the pureNi foils with different thicknesses. The deflection and load are measured byemploying the sequence pulse counting method and a high sensitive microload-sensor, respectively. All experimental results are analyzed usingcouple stress theory by Fleck and Hutchinson in which only rotation gradientis considered. Based on the plane-strain model we have derived the differentialequations and boundary conditions, which include the effect of couplestress. The differential equations are solved by the Runge-Kutta method. Thenumerical results are compared with the experimental data. There is no anyfitting parameter in the present theoretical calculation. All materialparameters are taken from the experimental measurements. The length scale istaken from the work of Stolken and Evans 2. The present theoreticalpredictions are in good agreement with the experimental data.