Interfacial modification and impact properties of Nb/MoSi₂ laminate composites by the addition of ZrO₂, NbSi₂, and SiC particles

In this study, the results of a thermodynamical estimation indicate that the impact properties of Nb/MoSi₂ laminate composites can be improved by suppressing the interfacial reaction. The effects of addition of SiC, NbSi₂, and ZrO₂ on the impact properties and interfacial reaction of Nb/MoSi₂ laminate composites are also examined. Laminate composites, which comprise alternate layers of matrix mixture and Nb foil, were fabricated by the hot press process. Addition of ZrO₂ particle is clearly demonstrated to increase both the impact value and the sintered density of Nb/MoSi₂ laminate composites. The thickness of the interfacial reaction layer in Nb/MoSi₂ laminate composites dramatically decreases with increasing volume fraction of ZrO₂ particle. The suppression of the interfacial reaction is caused by the formation of ZrSiO₄ in the MoSi₂-ZrO₂ matrix mixture. In addition, it appears that the reduction of the reaction layer promotes the plastic deformation of Nb foil and the interfacial delamination in laminate composites.