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A new class of light or reactive elements and monophase α′-matrix magnesium- and aluminum-based alloys with superior engineering properties, for the latter being based on a homogeneous solute distribution or a corrosion-resistant and metallic shiny surface withstanding aqueous and saline environment

A new class of light or reactive elements and monophase α′-matrix magnesium- and aluminum-based alloys with superior engineering properties, for the latter being based on a homogeneous solute distribution or a corrosion-resistant and metallic shiny surface withstanding aqueous and saline environments and resulting from the control during synthesis of atomic structure over microstructure to net shape of the final product, said α′-matrix being retained upon conversion into a cast or wrought form. The manufacture of the materials relies on the control of deposition temperature and in-vacuum consolidation during vapor deposition, on maximized heat transfer or casting pressure during all-liquid processing and on controlled friction and shock power during solid state alloying using a mechanical milling technique. The alloy synthesis is followed by extrusion, rolling, forging, drawing and superplastic forming for which the conditions of mechanical working, thermal exposure and time to transfer corresponding metastable α′-matrix phases and microstructure into product form depend on thermal stability and transformation behavior at higher temperatures of said light alloy as well as on the defects inherent to a specific alloy synthesis employed. Alloying additions to the resulting α′-monophase matrix include 0.1 to 40 wt. % metalloids or light rare earth or early transition or simple or heavy rare earth metals or a combination thereof. The eventually more complex light alloys are designed to retain the low density and to improve damage tolerance of corresponding base metals and may include an artificial aging upon thermomechanical processing with or without solid solution heat and quench and annealing treatment for a controlled volume fraction and size of solid state precipitates to reinforce alloy film, layer or bulk and resulting surface qualities. Novel processes are employed to spur production and productivity for the new materials.

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1. A magnesium-based alloy made by a chill-block casting technique,said magnesium-based alloy comprising a porosity-free microstructure and at least one alloying element or alloying addition in a solid solution and said chill-block casting technique being selected from the group consisting of contin

1. A magnesium-based alloy made by a chill-block casting technique,said magnesium-based alloy comprising a porosity-free microstructure and at least one alloying element or alloying addition in a solid solution and said chill-block casting technique being selected from the group consisting of continuous chill block casting, thin-strip casting, twin-roller quenching, thin-wall casting, pressure die casting to a wall thickness less than 20 mm, planar flow casting and melt spinning, wherein said porosity-free microstructure comprises a homogeneous distribution of at least one solute atom of the at least one alloying element or alloying addition and a maximum content of critical impurities by weight of 0.0005% Ni, 0.0013% Fe and 0.0005% Cu and no corrosion-rate controlling Fe inclusion, and wherein said porosity-free microstructure is in an as-solidified state or after an alloy conversion selected from the group consisting of one or more of the following: a thermo-mechanical treatment or rolling or superplastic forming, a hot forming operation or hot pressing, a forging or an extrusion, a communition to flakes or powder and a forging or an extrusion, a cold pressing or a cold isostatic pressing, a solution or homogenisation heat treatment, a thermo-mechanical treatment or a hot forming operation at temperatures according to a solution heat treatment, a quenching of a resulting product form, and an annealing treatment. 2. The magnesium-based alloy according to claim 1, wherein said porosity-free microstructure comprises in said as-solidified state further one or more of the following:A. a micrograined microstructure; B. a micrograined microstructure comprising grains, cells or subcells, wherein the grains, cells or subcells have one or more dimensions <10 μm; C. a micrograined microstructure comprising a columnar featureless or partition-less growth; D. a planar or columnar featureless or partitionless growth without a segregation; or; E. a micrograined microstructure comprising grains, cells or subcells, wherein the grains, cells or subcells have one or more dimensions <10 μm and a columnar featureless or partitionless growth. 3. The magnesium-based alloy according to claim 1, wherein said chill-block casting or quenching technique comprises one or more of the following:A. employing a a Mg feedstock of purity grade 3N8 or greater which comprises a maximum content by weight of 0.0005% Ni, 0.0013% Fe, 0.0005% Cu and 0.005% Na; B. casting under an inert atmosphere in order to protect a molten feedstock, a solidification operation or a resulting product or to maximize a heat extraction by a chill-block, wherein the inert atmosphere is selected from the group consisting of an inert-gas, a helium, an argon, a nitrogen, a mixture of helium with another inert gas, a hydrogen, a krypton, a neon, a xenon and a vacuum; C. casting into using an inert crucible material, wherein the inert crucible material is selected from the group consisting of a refractory metal, a tantalum-based material, a tantalum-based alloy, a refractory alloy and a refractory intermetallic phase; D. using an inert refractory metal, an inert refractory alloy, an inert intermetallic phase, a tantalum material or a tantalum-based alloy for contact with a condensed constituent of said magnesium alloy during a melting operation; or E. employing a highly conductive chill-block material. 4. The magnesium-based alloy according to claims 1 or 3, wherein said continuous chill-block casting or quenching, said thin strip casting, said twin roller quenching, said planar flow casting and said melt spinning comprises one or more of the following:A. employing a constrained fluid flow of a magnesium alloy melt to a chill-block for limitation of an extension of a solidification structure or a resulting dimension, thickness or width of an as-solidified product; B. employing a constrained melt puddle of a magnesium alloy melt to a chill-block for limitation or control of a resulting dimension, thickness or width of an as-solidified product; C. using a controlled distance between a casting nozzle and a chill-block; D. using a rectangular slot orifice as a casting nozzle in proximity to a chill-block; E. using a scraper to reduce an inert gas film or to improve contact and heat transfer between a rotating chill-block and a resulting as-solidified product; or F. employing a controlled surface speed of a chill-block. 5. The magnesium-based alloy according to claim 3, wherein said highly conductive chill-block material includes Cu.6. The magnesium-based alloy according to claim 1, wherein the magnesium-based alloy comprises further one or more of the following:A. an as-solidified cross-section of a thickness in the range from 200 nm to 500 mm; B. an as-solidified cross-section of a thickness in the range from 1 μm to 50 mm; C. an as-cast wall thickness in the range from 0.2 to 20 mm; or D. an as-cast wall thickness in the range from 0.5 to 10 mm. 7. A magnesium-based alloy made by a spray forming technique,said magnesium-based alloy comprising a porosity-free microstructure and at least one alloying element or alloying addition in a solid solution and said spray forming technique being selected from the group consisting of spray deposition and spray deposition using a linear atomizer concept, wherein said porosity-free microstructure comprises a homogeneous distribution of at least one solute atom of the at least one alloying element or alloying addition and a maximum content of critical impurities by weight of 0.0005% Ni, 0.0013% Fe and 0.0005% Cu and no corrosion-rate controlling Fe inclusion, and wherein said porosity-free microstructure after an alloy conversion selected from the group consisting of one or more of the following: a thermo-mechanical treatment or rolling or superplastic forming, a hot forming operation or hot pressing or hot isostatic pressing, a forging or an extrusion, a communition to flakes or powder and a forging or an extrusion, a cold pressing or a cold isostatic pressing, a solution or homogenization heat treatment, a thermo-mechanical treatment or a hot forming operation at temperatures according to a solution heat treatment, a quenching of a resulting product form, and an annealing treatment wherein said spray forming employs a Mg feedstock of purity grade 3N8 or greater which comprises a maximum content by weight of 0.0005% Ni, 0.0013% Fe, 0.0005% Cu and 0.005% Na and an inert atmosphere in order to protect a molten feedstock, a solidification operation or a resulting product, wherein the inert atmosphere is selected from the group consisting of an inert gas, helium, argon, nitrogen, a mixture of helium with another inert gas, hydrogen, krypton, neon, xenon and a vacuum. 8. The magnesium-based alloy according to claims 1 or 7, wherein said porosity-free microstructure comprises further one or more of the following:A. no corrosion-rate controlling pore; B. no pore having a pore size greater than a value in the range from 0.05 to 10 μm after a final forming operation; C. a close-packed-hexagonal alloy matrix; D. a grain size in the range from 0.5 to 8 μm; E. a grain size in the range from 0.2 to 10 μm; F. a grain having a high angle boundary and a size in the range from 0.5 to 8 μm; G. a grain having a high angle boundary and a size in the range from 0.2 to 10; H. a grain size in the range from 5 to 50 μm; I. a grain size in the range from 3 to 250 μm; J. a cell having a low angle boundary; K. a microstructure without microalloyed constituents on grain boundaries; L. a supersaturated microstructure; M. a one-phase microstructure; N. a supersaturated one-phase microstructure; or O. a majority of atoms in contact with impurity atoms being magnesium. 9. The magnesium-based alloy according to claims 1 or 7, wherein said alloy conversion comprises one or more of the following:A. said thermo-mechanical treatment or said hot forming operation at a temperature in vicinity of a eutectic or peritectic temperature; B. said rolling at a rolling speed at roll surface ranging from 0.05 to 100 m/min; C. said rolling at a rolling temperature of a rolling stock in a range from 100° to 500° C. or from 360° to 560° C. or from 390° to 480° C. or from 220° to 560° C. or from 200° to 560° C. or from 250° to 500° C.; D. said superplastic forming at a strain rate in the range from 8×10?1 to 10?5/sec or from 10?1 to 10?3/sec; E. said hot pressing at a temperature in the range from 60° to 550° C. after a degassing treatment or comprising hot isostatic pressing for 1 to 6 hours at a temperature in the range from 100° to 450° C.; F. said forging selected from a closed-die forging method and an open-die forging methods; G. said forging at a forging temperature of a forging in a range from 50° to 520° C. or from 170° to 450° C. or from 360° to 560° C. or from 380° to 480° C. or from 200° to 560° C. or from 25° to 450° C.; H. said cold pressing or said cold isostatic pressing comprising pressing at a pressure in the range from 50 to 1400 MPa; I. said solution or homogenization heat treatment being employed before or after or before and after said rolling or said forging or between rolling passes; J. said thermo-mechanical treatment or said hot forming operation at temperatures according to said solution heat treatment, wherein said solution heat treatment is for a period in the range from 0.25 to 1000 hours at a temperature in vicinity of a eutectic or peritectic temperature; K. said quenching of said resulting product form comprising quenching said resulting product form in oil or water at a temperature in the range from 10° to 90° C.; or L. said annealing treatment is for a period in the range from 0.1 to 10 hours at a temperature in the range from 60° to 120° C. or for a period in the range from 1 to 5 hours at a temperature in the range from 80° to 100° C. 10. The magnesium-based alloy according to claims 1 or 7, wherein the magnesium-based alloy comprises one or more of the following:A. a concentration of the at least one alloying element or alloying addition within an equilibrium solid solubility range of close-packed-hexagonal magnesium; B. a concentration of the at least one alloying element or alloying addition within the 1.5 fold amount of an equilibrium solid solubility range of close-packed-hexagonal magnesium; C. a high purity commercial alloy concentration selected from the group consisting of AZ-magnesium alloy series, AM-magnesium alloy series and AS-magnesium alloy series; or D. a high purity commercial alloy concentration selected from the group consisting of AZ9I, AZ61, AZ31, AM2O, AMSO, AM6O, AS41, AS42, ASH, AE42, WB43, WES4, ZE63, ZE41, EZ33 and EZ32. 11. The magnesium-based alloy according to claims 1 or 7, wherein the at least one alloying element or alloying addition for said continuous chill block casting, said twin-roller quenching, said rapid solidification, said planar flow casting and said melt spinning is selected from the group consisting of:0.1 to 25% by weight of La, 0.1 to 25% by weight of Ce, 0.1 to 25% by weight of Pr, 0.1 to 28% by weight of Nd, 0.1 to 30% by weight of Sm, 0.2 to 14% by weight of Y, 0.2 to 14% by weight of Y and Eu, 0.2 to 30% by weight of a light rare earth misch-metal, 0.2 to 15% by weight of Al, 0.1 to 10% by weight of Mn, and 0.1 to 5% by weight of Zr. 12. The magnesium-based alloy according to claims 1 or 7, wherein the at least one alloying element or alloying addition for said thin-wall casting, said pressure die casting to a wall thickness <20 mm and said rapid solidification being selected from the group consisting of:0.1 to 20% by weight of Sc, 0.1 to 7% by weight of Sm, 0.1 to 5% by weight of Gd, 0.1 to 7% by weight of Dy, 0.1 to 6% by weight of Ho, 0.1 to 7% by weight of Tm, 0.1 to 8% by weight of Er, 0.1 to 9% by weight of Lu, 0.1 to 6% by weight of Th, 0.1 to 2.5% by weight of Zr, and 0.1 to 3.0% by weight of Mn. 13. The magnesium-based alloy according to claims 1 or 7, wherein the magnesium-based alloy comprises one or more of the following ternary or higher order alloying elements:A. 0.1 to 5 wt. % La; B. 0.1 to 5 wt. % Ce; C. 0.1 to 5 wt. % Pr; D. 0.1 to 5 wt. % Nd; E. 0.1 to 5 wt. % light rare earth misch-metal; F. 0.1 to 8 wt. % Al; G. 0.1 to S wt. % alkaline earth metal and 0.1 to 8 wt. % Al; H. 0.1 to 5 wt. % alkaline earth metal and 0.1 to 8 wt. % Ga; I. 0.1 to 5 wt. % calcium and 0.1 to 8 wt. % Al; J. 0.1 to 5 wt. % strontium and 0.1 to 8 wt. % Al; K. 0.1 to 5 wt. % barium and 0.1 to 8 wt. % Al; L. 0.1 to 5 wt. % calcium and 0.1 to 8 wt. % Ga; M. 0.1 to 5 wt. % strontium and 0.1 to 8 wt. % Ga; N. 0.1 to 5 wt. % barium and 0.1 to 8 wt. % Ga; O. 0.1 to S wt. % Zn for a Mg-“yttric”-containing alloy; P. 0.1 to 5 wt. % M; or Q. 0.1 to 2 wt. % Zr.