Additive manufacture of multistable structures

Residual thermal stresses which develop during additive manufacturing processes are often a cause of unwanted component deformation and mechanical failure. We demonstrate that this impairment can in fact be exploited to enhance the design process for shell structures, where bistability is known to emerge in particular instances due to the presence of inelastic stresses. Multistable structures are produced through a single additive manufacturing operation by considering the inherent availability of thermal stresses in certain additive technologies. This concept is demonstrated through an analytical example, numerical simulations and a physical demonstrator produced via selective laser sintering of a titanium alloy. Our findings underline these hitherto untapped capabilities of additive processes and facilitate a deeper understanding of the thermal stresses developed during manufacture.