In this paper, the graphene oxide (GO) doped transition metal (Cu, Co, and Ni) complexes of triaminoguanidine (TAG) have been prepared where the GO serves as the stabilizing agent. The catalytic reactivity of GO stabilized TAG-M (M = Cu, Co, Ni) energetic composites on thermolysis of 1,3,5-trinitro-1,3,5-triazinane (RDX) has been investigated by using DSC/TGA techniques. It has been found that these materials have strong catalytic effects on decomposition of RDX by decreasing the apparent activation energy. Meantime, GO would not only stabilize TAG-M energetic composites but also enhance the thermal stability of RDX due to its high thermal conductivity. The physical models that govern the decomposition processes were also studied, and it has been shown that different reaction processes are accomplished by varying transition metals or in cooperation with GO. The complex catalyst, with improved thermal stability, represents a unique class of catalyst of considerable value for catalytic combustion and safety issue of solid propellants.

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A Ti-5Cu alloy produced by selective laser melting exhibits a nonuniform Ti2Cu phase structure, which contains a small amount of α′ phase in melt pool boundaries thereby resulting in reduced corrosion resistance. The heat-treatment process proposed in this work eliminates the deleterious effect of α′ phase and the Ti2Cu phase is refined using different cooling rates, which improves the corrosion resistance. The electrochemical results indicate that the heat-treated Ti-5Cu samples have similar corrosion behavior to pure CP-Ti. A slower cooling rate produces a larger spacing between the Ti2Cu phases in the microstructure of the sample, resulting in higher corrosion resistance. The corrosion behavior of SLM-produced Ti-5Cu and heat-treated counterparts with different microstructure are detailed discussed.

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ternary peritectic alloy, metastable immiscibility, rapid solidification, reduced gravity, liquid phase separation Since the 1990s, an outstanding giant magnetoresistance effect has been discovered in some peritectic alloys, such as Cu-Co, Cu-Co-Ni, Cu-Fe-Co, and so on. However, these alloys show a metastable miscibility gap in the undercooled state. During solidification, the uniform alloy melt tends to separate into two liquids with different compositions if undercooling exceeds the corresponding critical value. The metastable miscibility and rapid solidification of such alloys have attracted extensive interest in the field of both condensed matter physics and materials science [1][2][3][4] . In 1958, Nakagawa [5] observed the metastable liquid phase separation in Cu-Co and Cu-Fe alloys when measuring their magnetic susceptibility during successive cooling. He found that the uniform alloy melts separated into a Co-rich (or Fe-rich) and a Cu-rich liquid phase under the large undercooling