The compression response of extruded aluminum 6061‐T6 corrugated core sandwich columns is investigated. Analytical equations that predict the collapse load are used to generate failure mechanism maps. From these maps dominant failure mechanisms can be identified as a function of various geometric parameters and material properties. Experimental testing and numerical simulations are performed to test the fidelity of the analytical predictions. Fabrication of the sandwich panels involves extrusion of an aluminum billet through a specially designed die. To create longer columns the extruded panels are joined together using friction stir welding (FSW). Studies of the thermo‐mechanically affected zone (TMAZ) show that the hardness within these regions drops by approximately 50%. This significantly influences the observed failure load and failure mechanism and hence heat treatment post welding is required to ensure uniformity of properties. Good agreement is achieved between the predictions and experiment. Lastly, optimal designs are calculated based on the analytical analysis and results compared with hat‐stiffened and truss core sandwich columns.