Piyas Chowdhury's blog

Recent literature suggests that nano-twinned materials posses both high strength and ductility. Such unusual properties have been attributed to the unique ability of coherent twin boundaries in affecting dislocation slip transfer mechanisms unlike other types of grain boundaries of lesser symmetry. A combination of experimental and theoretical studies is presented to rationalize the macroscale attributes of nano-twinned NiCo alloys of four different compositions (please see the attached pdf below for the paper). 

The presence of nano-sized coherent precipitates is well known to have crucial impact on the mechanical behaviors of a broad class of shape memory alloys. The local stress gradient at the matrix-precipitate interface is predicted as induced by inter-lattice atomic disregistry. Due to the presence of the local disturbance fields, the preference for activating different martensitic variants, given the uni-directionality thereof, is influenced substantially.

Improtance of modeling fatigue damage propagation is substantial given the ubiquity of fatigue-induced component failures across industries. A review of fatigue crack growth models along with a detailed discussion of recent experimental findings (substantiating the model assumptions) are presented (please see the pdf attachment below)

Various outcomes of slip-coherent twin boundary depending on the stress state and slip geometry (during the growth of a microstructurally short crack)