Methods of making magnesium-based alloy components, such as automotive components, include treating a casting comprising a magnesium-based alloy to a first deforming process to form a preform. In one aspect, the first deforming process has a first maximum predetermined strain rate of greater than or equal to about 0.001/s to less than or equal to about 1/s in an environment having a temperature of ≥to about 250° C. to ≤to about 450° C. In another aspect, the first deforming process is cold deforming that is followed by annealing. The preform is then subjected to a second deforming process having a second maximum predetermined strain rate of ≥about 1/s to ≤about 100/s in an environment having a temperature of ≥about 150° C. to ≤about 450° C. to form the magnesium-based alloy component substantially free of cracking. A solid magnesium-based alloy component having select microstructures are also provided.

A high strength and corrosion-resistant magnesium alloy material, comprising 0.01-1.2 wt % of Ge and 0.01-1.2 wt % of Zn. A high strength and corrosion-resistant magnesium alloy material, comprising the following chemical elements in percentage by weight: Ge: 0.01-1.2%; Zn: 0.01-1.2%; at least one of Mn, Ca, Zr, Sr, and Gd, with a total weight percentage of ≤3%, wherein the percentage by weight of a single element is ≤0.8%; and the balance of Mg and other inevitable impurities. A method for fabricating the above mentioned high strength and corrosion-resistant magnesium alloy material, comprising the steps of: smelting, solid solution heat treatment, and extrusion, wherein in the extrusion step, the extrusion temperature is 180-350° C., the extrusion rate is 0.1-10 mm/s, and the extrusion ratio is 10:1-30:1.

A high strength and corrosion-resistant magnesium alloy material, comprising 0.01-1.2 wt % of Ge and 0.01-1.2 wt % of Zn. A high strength and corrosion-resistant magnesium alloy material, comprising the following chemical elements in percentage by weight: Ge: 0.01-1.2%; Zn: 0.01-1.2%; at least one of Mn, Ca, Zr, Sr, and Gd, with a total weight percentage of ≤3%, wherein the percentage by weight of a single element is ≤0.8%; and the balance of Mg and other inevitable impurities. A method for fabricating the above mentioned high strength and corrosion-resistant magnesium alloy material, comprising the steps of: smelting, solid solution heat treatment, and extrusion, wherein in the extrusion step, the extrusion temperature is 180-350° C., the extrusion rate is 0.1-10 mm/s, and the extrusion ratio is 10:1-30:1.

A bioerodible endoprosthesis includes a bioerodible magnesium alloy. The bioerodible magnesium alloy has magnesium and one or more additional alloying elements, including aluminum. The alloy has a microstructure comprising equiaxed Mg-rich solid solution phase grains having an average grain diameter of less than or equal to 5 microns and continuous or discontinuous second-phase precipitates in grain boundaries between the Mg-rich solid solution-phase grains, the second-phase precipitates having an average longest dimension of 0.5 micron or less.

A bioerodible endoprosthesis includes a bioerodible magnesium alloy. The bioerodible magnesium alloy has magnesium and one or more additional alloying elements, including aluminum. The alloy has a microstructure comprising equiaxed Mg-rich solid solution phase grains having an average grain diameter of less than or equal to 5 microns and continuous or discontinuous second-phase precipitates in grain boundaries between the Mg-rich solid solution-phase grains, the second-phase precipitates having an average longest dimension of 0.5 micron or less.

A preferred embodiment is an uncoated, biodegradable stent. The stent has a filigree structure of magnesium alloy struts. The struts of the supporting structure are arranged to permit a compressed form for introduction into the body and to permit an expanded form at the site of the application within a vessel. The magnesium alloy struts are formed of a corrodible magnesium alloy. The magnesium alloy is formed from high-purity vacuum distilled magnesium containing impurities, which promote electrochemical potential differences and/or the formation of precipitations and/or intermetallic phases. The impurities are such that the struts of the stent have a tensile strength of >275 MPa a yield point of >200 MPa, a yield ratio of <0.8, a difference between tensile strength and yield point of >50 MPa.

A preferred embodiment is an uncoated, biodegradable stent. The stent has a filigree structure of magnesium alloy struts. The struts of the supporting structure are arranged to permit a compressed form for introduction into the body and to permit an expanded form at the site of the application within a vessel. The magnesium alloy struts are formed of a corrodible magnesium alloy. The magnesium alloy is formed from high-purity vacuum distilled magnesium containing impurities, which promote electrochemical potential differences and/or the formation of precipitations and/or intermetallic phases. The impurities are such that the struts of the stent have a tensile strength of >275 MPa a yield point of >200 MPa, a yield ratio of <0.8, a difference between tensile strength and yield point of >50 MPa.

A magnesium alloy sheet containing, relative to 100 wt % of the entire magnesium alloy sheet, 2.7 to 5.0 wt % of Al, 0.75 to 1.0 wt % of Zn, 0.1 to 1.0 wt % of Ca, 1.0 wt % or less of Mn (excluding 0 wt %), and the balance of Mg and other inevitable impurities, wherein a volume fraction of bottom crystal grains, relative to 100 vol % of overall crystal grains of the magnesium alloy sheet, is 30% or less, and the bottom crystal grains are crystal grains in a <0001>//C-axis direction.

A magnesium alloy sheet containing, relative to 100 wt % of the entire magnesium alloy sheet, 2.7 to 5.0 wt % of Al, 0.75 to 1.0 wt % of Zn, 0.1 to 1.0 wt % of Ca, 1.0 wt % or less of Mn (excluding 0 wt %), and the balance of Mg and other inevitable impurities, wherein a volume fraction of bottom crystal grains, relative to 100 vol % of overall crystal grains of the magnesium alloy sheet, is 30% or less, and the bottom crystal grains are crystal grains in a <0001>//C-axis direction.

A method for heat treating metal materials by passing electrical current through a metallic workpiece to heat the workpiece via Joule heating to a preselected temperature for a preselected period of time, based upon the formula I.sup.2×R×t, wherein I is current, R is resistance and t is time. The current may be a direct or an alternating one. Various configurations of the method are envisioned wherein multiple current inputs and outputs are attached to the metal material so as to selectively heat specific portions of the piece including irregular shapes and differing diameters.