B1-type and WC-type phase bulk bodies of tantalum nitride prepared by shock and static compressions

Tantalum nitride (TaN) is a unique nitride which has CoSn-type structure at ambient state among the transition metal nitrides (1:1). We have been performing the shock-and static-high-pressure compression experiments to synthesize the dense-phase tantalum nitrides. The single-phase bulk body of B1-type tantalum nitride with good stoichiornetry was prepared by shock compression. The single-phase bulk bodies of B1-and WC-type tantalum nitrides were also prepared by static compression. The static-compression quenching experiments showed that the B1-type phase was a high-temperature high-pressure phase and the WC-type phase was a low-temperature high-pressure phase. The B1-and WC-type phases bulk bodies had good high-temperature stabilities and much higher hardnesses than the CoSn-type. The shock-compression-synthesized B1-type one showed superconductivity with a comparatively high critical temperature.