A nanometre-sized porous phase in iron–carbon–boron system

A porous phase is detected in a Fe–0.28wt.%C–0.1wt.%B alloy. The porous phase is mainly located at the grain boundary region and the pore size ranges from about 10nm to 500nm. The chemical composition of the porous phase is very close to Fe3(B0.7C0.3) with an orthorhombic lattice. The result shows an opportunity to produce bulk steel matrix composites with a porous second phase.