Adding multiple solute elements could create fracture origin through formation of intermetallic compound due to bonding of added elements. While maintaining microstructure for activating non-basal dislocation movement, additive elements not to create fracture origin, but to promote grain boundary sliding are preferably found from among inexpensive and versatile elements. Provided is Mg-based wrought alloy material including two or more among group consisting of Mn, Zr, Bi, and Sn; and Mg and unavoidable constituents, having excellent room-temperature ductility and characterized by having finer crystal grain size in Mg parent phase during room-temperature deformation and in that mean grain size in matrix thereof is 20 μm or smaller; rate of (σ.sub.max−σ.sub.bk)/σ.sub.max (maximum load stress (σ.sub.max), breaking stress (σ.sub.bk)) in stress-strain curve obtained by tension-compression test of the wrought material is 0.2 or higher; and resistance against breakage shows 200 kJ or higher.

Adding multiple solute elements could create fracture origin through formation of intermetallic compound due to bonding of added elements. While maintaining microstructure for activating non-basal dislocation movement, additive elements not to create fracture origin, but to promote grain boundary sliding are preferably found from among inexpensive and versatile elements. Provided is Mg-based wrought alloy material including two or more among group consisting of Mn, Zr, Bi, and Sn; and Mg and unavoidable constituents, having excellent room-temperature ductility and characterized by having finer crystal grain size in Mg parent phase during room-temperature deformation and in that mean grain size in matrix thereof is 20 μm or smaller; rate of (σ.sub.max−σ.sub.bk)/σ.sub.max (maximum load stress (σ.sub.max), breaking stress (σ.sub.bk)) in stress-strain curve obtained by tension-compression test of the wrought material is 0.2 or higher; and resistance against breakage shows 200 kJ or higher.

A high-capacity and long-life negative electrode hydrogen storage material of La—Mg—Ni type for secondary rechargeable nickel-metal hydride battery and a method for preparing the same are provided in the present invention. A chemical formula of the negative electrode hydrogen storage material of La—Mg—Ni type is La.sub.1-x-yRe.sub.xMg.sub.y(Ni.sub.1-a-bAl.sub.aM.sub.b).sub.z, wherein Re is at least one of Ce, Pr, Nd, Sm, Y, and M is at least one of Ti, Cr, Mo, Nb, Ga, V, Si, Zn, Sn; 0≤x≤0.10, 0.3≤y≤0.5, 0<a≤0.05, 0≤b≤0.02, 2.3≤z<3.0. The negative electrode hydrogen storage material of La—Mg—Ni type in the present invention has excellent charge-discharge capacity and cycle life. The negative electrode hydrogen storage material of La—Mg—Ni type can be applied in both common secondary rechargeable nickel-metal hydride battery and secondary rechargeable nickel-metal hydride battery with ultra-low self-discharge and long-term storage performance.

A high-capacity and long-life negative electrode hydrogen storage material of La—Mg—Ni type for secondary rechargeable nickel-metal hydride battery and a method for preparing the same are provided in the present invention. A chemical formula of the negative electrode hydrogen storage material of La—Mg—Ni type is La.sub.1-x-yRe.sub.xMg.sub.y(Ni.sub.1-a-bAl.sub.aM.sub.b).sub.z, wherein Re is at least one of Ce, Pr, Nd, Sm, Y, and M is at least one of Ti, Cr, Mo, Nb, Ga, V, Si, Zn, Sn; 0≤x≤0.10, 0.3≤y≤0.5, 0<a≤0.05, 0≤b≤0.02, 2.3≤z<3.0. The negative electrode hydrogen storage material of La—Mg—Ni type in the present invention has excellent charge-discharge capacity and cycle life. The negative electrode hydrogen storage material of La—Mg—Ni type can be applied in both common secondary rechargeable nickel-metal hydride battery and secondary rechargeable nickel-metal hydride battery with ultra-low self-discharge and long-term storage performance.

The disclosure discloses a method of producing a magnesium alloy wheel hub, comprises the following steps: step 1, heating a magnesium alloy bar to 350-430° C. and keeping the temperature for 20 minutes; step 2, initially forging and forming the bar under a forging press, the forging speed is 6-15 mm/s; step 3, finally forging and forming the bar under a forging press, and the forging speed is 5-8 mm/s; step 4, testing the microstructure and material properties of the final forged blank to obtain the layered material property distribution on the thickness of the blank; step 5, according to the layered material property distribution on the thickness of the blank obtained in step 4, selecting the part that meets the requirements to make a magnesium alloy wheel hub. According to the different properties in the thickness direction of the blank, the spoke orientation of the magnesium alloy wheel can be quickly designed according to the needs, and the magnesium alloy wheel that meets the usage performance can be obtained, which greatly improves the design and processing efficiency.

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.

A variable stiffness engineered degradable ball or seal having a degradable phase and a stiffener material. The variable stiffness engineered degradable ball or seal can optionally be in the form of a degradable diverter ball or sealing element which can be made neutrally buoyant.

A variable stiffness engineered degradable ball or seal having a degradable phase and a stiffener material. The variable stiffness engineered degradable ball or seal can optionally be in the form of a degradable diverter ball or sealing element which can be made neutrally buoyant.

Provided is a magnesium alloy having a thermal conductivity of 75 W/m.Math.K or more and a high specific strength. One aspect of the present invention is a magnesium alloy containing a at. % of Al, b at. % of Ca, c at. % of Mn, and d at. % of D, with the remainder comprising Mg and unavoidable impurities. D has at least one of a rare-earth element (RE), Sn, Li, Zn, Ag, Be and Sc. The magnesium alloy does not contain Si and Sr. C mentioned above satisfies expression 1 below, d satisfies expression 2 below, and a and b are within a range enclosed by the solid line shown in FIG. 1. The thermal conductivity is 75 W/m.Math.K or greater.

0≤c≤0.1  (Expression 1)

0≤d≤1  (Expression 2)

Embodiments of the present disclosure provide for structures including an alloy of calcium, strontium, and magnesium.