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An apparatus and method of uniformly heating, rheologically softening, and thermoplastically forming metallic glasses rapidly into a net shape using a rapid capacitor discharge forming (RCDF) tool are provided. The RCDF method utilizes the discharge of electrical energy stored in a capacitor to unif

An apparatus and method of uniformly heating, rheologically softening, and thermoplastically forming metallic glasses rapidly into a net shape using a rapid capacitor discharge forming (RCDF) tool are provided. The RCDF method utilizes the discharge of electrical energy stored in a capacitor to uniformly and rapidly heat a sample or charge of metallic glass alloy to a predetermined “process temperature” between the glass transition temperature of the amorphous material and the equilibrium melting point of the alloy in a time scale of several milliseconds or less. Once the sample is uniformly heated such that the entire sample block has a sufficiently low process viscosity it may be shaped into high quality amorphous bulk articles via any number of techniques including, for example, injection molding, dynamic forging, stamp forging, sheet forming, and blow molding in a time frame of less than 1 second.

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1. A method of rapidly and uniformly heating a metallic glass sheet using a rapid capacitor discharge comprising: providing a sample of metallic glass formed of a metallic glass forming alloy having a substantially uniform cross section in an enclosure, the enclosure having an opening in at least on

1. A method of rapidly and uniformly heating a metallic glass sheet using a rapid capacitor discharge comprising: providing a sample of metallic glass formed of a metallic glass forming alloy having a substantially uniform cross section in an enclosure, the enclosure having an opening in at least one end thereof and at least one pair of rollers arranged parallel to each other positioned external to said enclosure and adjacent to the opening;discharging a quantum of electrical energy of at least 50 Joules uniformly through said sample to uniformly heat the sample at a rate of at least 500K/sec to a processing temperature between the glass transition temperature of the metallic glass and the equilibrium melting point of the metallic glass forming alloy;applying a compressive force to the heated sample to urge said material through the opening and between the at least one roller pair, the roller pair being configured to apply a deformational force to shape the heated sample into a sheet while the heated sample is still at a temperature between the glass transition temperature of the metallic glass and the equilibrium melting point of the metallic glass forming alloy; andcooling said article to a temperature below the glass transition temperature of the metallic glass. 2. The method of claim 1, wherein the metallic glass has a resistivity that does not increase with temperature. 3. The method of claim 1, wherein the metallic glass has a relative change of resistivity per unit of temperature change (S) of no greater than about 1×10−4° C.−1 and a resistivity at room temperature (ρ0) between about 80 and 300 μΩ-cm. 4. The method of claim 1, wherein the quantum of electrical energy is discharged at a discharge time constant of between about 10 μs and 100 ms. 5. The method of claim 1, wherein the processing temperature is about halfway between the glass transition temperature of the metallic glass and the equilibrium melting point of the metallic glass forming alloy. 6. The method of claim 1, wherein the processing temperature is such that the viscosity of the heated metallic glass is from about 1 to 104 Pas-sec. 7. The method of claim 1, wherein the sample is substantially defect free. 8. The method of claim 1, wherein the metallic glass is an alloy based on an elemental metal selected from the group consisting of Zr, Pd, Pt, Au, Fe, Co, Ti, Al, Mg, Ni and Cu. 9. The method of claim 1, wherein the step of discharging said quantum of electrical energy generates an electrical field in said sample, and wherein the electromagnetic skin depth of the dynamic electric field generated is large compared to the radius, width, thickness, and length of the sample. 10. The method of claim 1, wherein the enclosure is electrically non-conductive. 11. The method of claim 1, wherein the sample is urged by a plunger, and wherein said plunger comprises an outer surface, wherein at least the outer surface of said plunger is electrically non-conductive. 12. The method of claim 1, wherein at least the outer surfaces of the at least one pair of rollers are electrically non-conductive. 13. The method of claim 1, comprising at least two pair of rollers arranged in series downstream from the opening. 14. The method of claim 13, wherein the outer surfaces of at least the pair of rollers downstream of the pair of rollers positioned adjacent to the opening are thermally conductive. 15. The method of claim 14, wherein the thermally conductive rollers are made of copper, a copper-beryllium alloy, brass, aluminum, or steel. 16. The method of claim 1, wherein the step of discharging said quantum of electrical energy occurs through at least two electrodes connected to opposite ends of said sample. 17. The method of claim 1, wherein the rollers are rotated at a speed ω in [rpm] such that: 30⁢r2Rb⁢⁢τ<ω<30⁢r2⁢DRb3where (r) is the diameter of the amorphous material sample, (R) is the diameter of each of the at least one pair of rollers, (b) is the distance between the rollers, (D) is the thermal diffusivity of the amorphous material, and (τ) is the time that the amorphous material crystallizes at the processing temperature. 18. The method of claim 1, wherein the rollers rotate at a speed between 10 and 10,000 rpm. 19. The method of claim 1, wherein the distance between the individual rollers of the at least one pair is between 0.1 and 1 mm. 20. The method of claim 1, wherein the heating and ejecting of the sample through the opening and between the at least one roller pair are complete in a time of between about 100 μs to 1 s. 21. The method of claim 1, wherein the compressive force to the heated amorphous metal is applied after the discharge of electrical energy is completed. 22. The method of claim 21, wherein the application of compressive force is controlled by an actuating mechanism that involves voltage/current sensing with pneumatic, hydraulic, magnetic or electric motion. 23. The method of claim 1, wherein the quantum of electrical energy is at least about 100 joules.