Provided is Mg-based alloy wrought material having improved ductility, formality, and resistance against fracture. Intermetallic compounds may be formed by mutual bonding of added elements to be a fracture origin. While maintaining microstructure for activating non-basal dislocation movement of Mg-based alloy wrought material, added elements to create no fracture origin, but to promote grain boundary sliding were found from among inexpensive and versatile elements. Provided is Mg-based alloy wrought material including at least one element from Zr, Bi, and Sn and at least one element from Al, Zn, Ca, Li, Y, and Gd wherein remainder comprises Mg and unavoidable impurities; an average grain size in a parent phase is 20 μm or smaller; a value of (σ.sub.max−σ.sub.bk)/σ.sub.max (maximum load stress (σ.sub.max), breaking stress (σ.sub.bk)) in a stress-strain curve obtained by tension-compression tests of the wrought material is 0.2 or higher; and resistance against breakage shows 100 kJ or higher.

Provided is Mg-based alloy wrought material having improved ductility, formality, and resistance against fracture. Intermetallic compounds may be formed by mutual bonding of added elements to be a fracture origin. While maintaining microstructure for activating non-basal dislocation movement of Mg-based alloy wrought material, added elements to create no fracture origin, but to promote grain boundary sliding were found from among inexpensive and versatile elements. Provided is Mg-based alloy wrought material including at least one element from Zr, Bi, and Sn and at least one element from Al, Zn, Ca, Li, Y, and Gd wherein remainder comprises Mg and unavoidable impurities; an average grain size in a parent phase is 20 μm or smaller; a value of (σ.sub.max−σ.sub.bk)/σ.sub.max (maximum load stress (σ.sub.max), breaking stress (σ.sub.bk)) in a stress-strain curve obtained by tension-compression tests of the wrought material is 0.2 or higher; and resistance against breakage shows 100 kJ or higher.

A thermoelectric conversion material includes Mg.sub.2Si.sub.xSn.sub.1−x (where 0.3≤X≤1) and a boride containing one or two or more metals selected from titanium, zirconium, and hafnium. Further, it is preferable that the boride is one or two or more selected from TiB.sub.2, ZrB.sub.2, and HfB.sub.2.

A corrodible downhole article includes a magnesium alloy. The magnesium alloy includes: 1-9 wt % Zn; 1-2 wt % Cu; 0.5-1.0 wt % Mn; and 0.1-5 wt % of a corrosion promoting element (e.g., Ni). The alloy can have a 0.2% proof strength of at least 150 MPa when tested using standard tensile test method ASTM B557-10.

A corrodible downhole article includes a magnesium alloy. The magnesium alloy includes: 1-9 wt % Zn; 1-2 wt % Cu; 0.5-1.0 wt % Mn; and 0.1-5 wt % of a corrosion promoting element (e.g., Ni). The alloy can have a 0.2% proof strength of at least 150 MPa when tested using standard tensile test method ASTM B557-10.

According to one implementation, a magnesium-lithium alloy contains not less than 10.50 mass % and not more than 16.00 mass % lithium, not less than 5.00 mass % and not more than 12.00 mass % aluminum, and not less than 2.00 mass % and not more than 8.00 mass % calcium. According to one implementation, a rolled stock is made of the above-mentioned magnesium-lithium alloy. According to one implementation, a processed product includes the above-mentioned magnesium-lithium alloy as a material.

According to one implementation, a magnesium-lithium alloy contains not less than 10.50 mass % and not more than 16.00 mass % lithium, not less than 5.00 mass % and not more than 12.00 mass % aluminum, and not less than 2.00 mass % and not more than 8.00 mass % calcium. According to one implementation, a rolled stock is made of the above-mentioned magnesium-lithium alloy. According to one implementation, a processed product includes the above-mentioned magnesium-lithium alloy as a material.

The present disclosure provides a high-plasticity rapidly-degradable Mg-Li-Gd-Ni alloy, including the following chemical elements by mass percentage: 1.0-10.0% of Gd, 0.2-2.0% of Ni, 5.5-10% of Li, and the rest of Mg and inevitable impurities. The impurities have a total content less than or equal to 0.3%. The present disclosure further provides a preparation method of the high-plasticity rapidly-degradable Mg-Li-Gd-Ni alloy. The high-plasticity rapidly-degradable Mg-Li-Gd-Ni alloy provided by the present disclosure constructs an α-Mg+β-Li dual-phase matrix structure by introducing β-Li with a body-centered cubic (BCC) structure with relatively more slip systems to improve plasticity of the alloy, then adds a certain amount of Gd element to weaken texture and promote non-basal plane slip, and further improves plasticity. In addition, by introducing the high-potential Ni-containing LPSO phase, a large potential difference with α-Mg and β-Li is formed to increase the degradation performance.

The present disclosure provides a high-plasticity rapidly-degradable Mg-Li-Gd-Ni alloy, including the following chemical elements by mass percentage: 1.0-10.0% of Gd, 0.2-2.0% of Ni, 5.5-10% of Li, and the rest of Mg and inevitable impurities. The impurities have a total content less than or equal to 0.3%. The present disclosure further provides a preparation method of the high-plasticity rapidly-degradable Mg-Li-Gd-Ni alloy. The high-plasticity rapidly-degradable Mg-Li-Gd-Ni alloy provided by the present disclosure constructs an α-Mg+β-Li dual-phase matrix structure by introducing β-Li with a body-centered cubic (BCC) structure with relatively more slip systems to improve plasticity of the alloy, then adds a certain amount of Gd element to weaken texture and promote non-basal plane slip, and further improves plasticity. In addition, by introducing the high-potential Ni-containing LPSO phase, a large potential difference with α-Mg and β-Li is formed to increase the degradation performance.

The present invention provides a thermoelectric material excellent in heat resistance with less degradation of thermoelectric characteristics even in a high temperature environment. The thermoelectric material comprises a compound represented by a chemical formula Mg.sub.2Si.sub.1-xSn.sub.x (0<x<1) wherein at least one of the Si site and the Sn site of the compound is replaced with at least one of Sb and Bi, and an added Fe.