The structure of porous nickel titanium reinforced by monolithic nickel titanium

The structure and elemental composition of a composite representing porous nickel titanium reinforced by a monolithic nickel titanium rod (TN-10 alloy) have been studied. The structures of the initial TiNi powder (PN55T45S grade), the porous and monolithic parts of this composite, and the transition regions between these parts have been studied using a scanning electron microscope (SEM 515). Elemental compositions of the TiNi matrix phase and secondary phase inclusions were determined using an electron probe microanalyzer (JEOL JSM 840). It is established that there is no clear interface between the sintered porous and monolithic parts of the composite. Instead, the TiNi particles and monolithic TN-10 alloy rod exhibit complete mutual dissolution. The elemental composition of the TiNi matrix region exhibits rather insignificant variations between monolithic and porous parts.