INVESTIGATING THERMAL EFFECTS IN NONLINEAR BUCKLING ANALYSIS OF MICRO BEAMS USING MODIFIED STRAIN GRADIENT THEORY

In this paper, thermal effects in nonlinear buckling analysis of micro beams is investigated. Modified strain gradient theory with nonlinear von-Karman strain-displacement relations and small scale parameters are used to derive the buckling behavior of micro beams. The Poisson’s effect is included and its significance is demonstrated. Buckling behavior for two different cases: 1) immovable axial boundary condition 2) movable axial boundary condition, are studied and for each one the results for hinged-hinged and clamped-clamped beams are presented. The analysis shows that modified strain gradient theory leads to a higher critical buckling load in comparison with the classical and couple- stress theories. The results are verified using previous related works.