Buckling behavior of nickel microbeams based on reformulated strain gradient theory

In this paper, the microstructure-dependent buckling behavior of microbeams is investigated. The material used for the microbeams is chosen as nickel. The reformulated strain gradient theory and Euler-Bernoulli beam theory are employed to develop the microbeam model with size effect. Rayleigh-Ritz method is used to achieve the critical buckling loads for cantilever and simply supported microbeams. Buckling behavior and size effects based on classical and nonclassical theories are investigated and compared. Some different conditions, such as inclusion of length scale parameters and increasing the length and thickness of microbeam, and their effects on the critical buckling loads are studied. Also, some comparative results are presented to demonstrate the accuracy and validity of the present analysis. It is found that the size effects become more pronounced, especially on smaller slenderness ratios.