A magnesium-based thermoelectric conversion material includes a first layer formed of Mg.sub.2Si and a second layer formed of Mg.sub.2Si.sub.xSn.sub.1-x (here, x is equal to or greater than 0 and less than 1), in which the first layer and the second layer are directly joined to each other, and within a junction surface with the first layer and in the vicinity of the junction surface, the second layer has a tin concentration transition region in which a tin concentration increases as a distance from the junction surface increases. The junction layer is regarded as a site in which a tin concentration is found to be equal to or lower than a detection limit by the measurement performed using EDX.

High pressure presses, components for high pressure presses and related methods are provided herein. In one embodiment of the invention, a press base may include a piston cavity formed in the press base and a piston cavity sleeve positioned in the piston cavity. The piston cavity sleeve may include a wall having an outer surface and an inner surface opposite the outer surface. The piston cavity sleeve may further include a floor having an upper surface and a lower surface opposite the upper surface. An outer radius may be formed at a juncture of the outer surface of the wall and lower surface of the floor and an inner radius may be formed at a juncture of the inner surface of the wall and upper surface of the floor. The inner radius may exhibit a radius of curvature that is greater than a radius of curvature of the outer radius.

High pressure presses, components for high pressure presses and related methods are provided herein. In one embodiment of the invention, a press base may include a piston cavity formed in the press base and a piston cavity sleeve positioned in the piston cavity. The piston cavity sleeve may include a wall having an outer surface and an inner surface opposite the outer surface. The piston cavity sleeve may further include a floor having an upper surface and a lower surface opposite the upper surface. An outer radius may be formed at a juncture of the outer surface of the wall and lower surface of the floor and an inner radius may be formed at a juncture of the inner surface of the wall and upper surface of the floor. The inner radius may exhibit a radius of curvature that is greater than a radius of curvature of the outer radius.

Polycrystalline cubic boron nitride, PCBN, material and methods of making PCBN. A method includes providing a matrix precursor powder comprising particles having an average particle size no greater than 250 nm, providing a cubic boron nitride, cBN, powder comprising particles of cBN having an average particle size of at least 0.2 intimately mixing the matrix precursor powder and the cBN powder, and sintering the intimately mixed powders at a temperature of at least 1100° C. and a pressure of at least 3.5 GPa to form the PCBN material comprising particles of cubic boron nitride, cBN dispersed in a matrix material.

Polycrystalline cubic boron nitride, PCBN, material and methods of making PCBN. A method includes providing a matrix precursor powder comprising particles having an average particle size no greater than 250 nm, providing a cubic boron nitride, cBN, powder comprising particles of cBN having an average particle size of at least 0.2 intimately mixing the matrix precursor powder and the cBN powder, and sintering the intimately mixed powders at a temperature of at least 1100° C. and a pressure of at least 3.5 GPa to form the PCBN material comprising particles of cubic boron nitride, cBN dispersed in a matrix material.

A method for making small diameter NiTi metal alloy components, including balls, comprising providing a metal powder comprising nickel, titanium, and a transition metal, consolidating the metal powder into cylindrical rods, and cutting the cylindrical rods into segments. The segments are then machined into spheres slightly larger than the finished ball size diameter. The spheres are heat treated to solutionize and dissolve all phases and subsequently cooled without the need for rapid quenching due to the influence of the transition metal to suppresses the formation of soft phases in the spheres, wherein such soft phases prevent hardening, to achieve a Rockwell hardness of HRC 58-62. Finally, the hardened spheres are polished until the desired finished ball size diameter and surface finish is achieved.

A method for making small diameter NiTi metal alloy components, including balls, comprising providing a metal powder comprising nickel, titanium, and a transition metal, consolidating the metal powder into cylindrical rods, and cutting the cylindrical rods into segments. The segments are then machined into spheres slightly larger than the finished ball size diameter. The spheres are heat treated to solutionize and dissolve all phases and subsequently cooled without the need for rapid quenching due to the influence of the transition metal to suppresses the formation of soft phases in the spheres, wherein such soft phases prevent hardening, to achieve a Rockwell hardness of HRC 58-62. Finally, the hardened spheres are polished until the desired finished ball size diameter and surface finish is achieved.

A method for making small diameter NiTi metal alloy components, including balls, comprising providing a metal powder comprising nickel, titanium, and a transition metal, consolidating the metal powder into cylindrical rods, and cutting the cylindrical rods into segments. The segments are then machined into spheres slightly larger than the finished ball size diameter. The spheres are heat treated to solutionize and dissolve all phases and subsequently cooled without the need for rapid quenching due to the influence of the transition metal to suppresses the formation of soft phases in the spheres, wherein such soft phases prevent hardening, to achieve a Rockwell hardness of HRC 58-62. Finally, the hardened spheres are polished until the desired finished ball size diameter and surface finish is achieved.

A titanium aluminide (TiAl) coating capable of improving high-temperature oxidation resistance of titanium alloys and a preparation method thereof are provided. The TiAl coating includes α-AlF.sub.3 nanoparticles, and a content of the α-AlF.sub.3 nanoparticles is 5-30 vol. % of the TiAl coating. The preparation method of the TiAl coating includes: using a TiAl alloy target and an α-AlF.sub.3 target as raw materials, and performing magnetron sputtering on a substrate surface to prepare a coating; the magnetron sputtering is double-target co-sputtering, and a substrate temperature during the magnetron sputtering is 150° C., the TiAl alloy target is performed direct current sputtering with a power of 0.5-2 kW, and the α-AlF.sub.3 target is performed radio frequency sputtering with a power of 0.07-0.2 kW. After the coating is obtained by the double-target co-sputtering, the obtained coating is heat-treated at 600-800° C. for 5-20 h to obtain a final coating.

A titanium aluminide (TiAl) coating capable of improving high-temperature oxidation resistance of titanium alloys and a preparation method thereof are provided. The TiAl coating includes α-AlF.sub.3 nanoparticles, and a content of the α-AlF.sub.3 nanoparticles is 5-30 vol. % of the TiAl coating. The preparation method of the TiAl coating includes: using a TiAl alloy target and an α-AlF.sub.3 target as raw materials, and performing magnetron sputtering on a substrate surface to prepare a coating; the magnetron sputtering is double-target co-sputtering, and a substrate temperature during the magnetron sputtering is 150° C., the TiAl alloy target is performed direct current sputtering with a power of 0.5-2 kW, and the α-AlF.sub.3 target is performed radio frequency sputtering with a power of 0.07-0.2 kW. After the coating is obtained by the double-target co-sputtering, the obtained coating is heat-treated at 600-800° C. for 5-20 h to obtain a final coating.