Method for Forming Hollow Profile Non-Circular Extrusions Using Shear Assisted Processing and Extrusion (ShAPE)
A process for forming extruded products using a device having a scroll face configured to apply a rotational shearing force and an axial extrusion force to the same preselected location on material wherein a combination of the rotational shearing force and the axial extrusion force upon the same location cause a portion of the material to plasticize, flow and recombine in desired configurations. This process provides for a significant number of advantages and industrial applications, including but not limited to extruding tubes used for vehicle components with 50 to 100 percent greater ductility and energy absorption over conventional extrusion technologies, while dramatically reducing manufacturing costs.
1. A shear-assisted extrusion process for forming extrusions of a desired composition from feedstock material, the method comprising:
simultaneously applying a rotational shearing force and an axial extrusion force to the same location on the feedstock material using a scroll of a die having a scroll face with a plurality of grooves defined therein by pushing the scroll face into the feedstock material while the scroll is rotated relative to the feedstock material to plasticize the feedstock material against the scroll face, the grooves configured to direct plasticized feedstock material from a first location at the interface between the feedstock material and the scroll face through the due via a portal defined within the scroll face to a second location on a die bearing surface where the plasticized feedstock material recombines at the die bearing surface to form the extrusions.
2. The process of claim 1 wherein the scroll has multiple portals, each portal configured to direct plasticized material through the scroll face.
3. The process of claim 2 wherein the grooves on the scroll face comprise a first set of grooves configured to direct plasticized material in a first direction and a second set of grooves configured to direct plasticized in a second direction different from the first direction.
4. The process of claim 3 wherein extrusion of the plasticized material is performed at a die face temperature less than 150° C.
5. The process of claim 3 wherein the axial extrusion force is at or below 50 MPa.
6. The process of claim 3 wherein the feedstock material is in a powder form.
7. The process of claim 3 wherein the feedstock material is a magnesium alloy in billet form, the axial extrusion force is at or below 25 MPa, and temperature is less than 100° C.
8. A device for performing shear assisted extrusion comprising:
a die comprising a scroll face configured to apply a rotational shearing force and an axial extrusion force to the same preselected location on the feedstock material by pushing the scroll face into the feedstock material while the scroll is rotated relative to the feedstock material to plasticize the feedstock material against the scroll face wherein a combination of the rotational shearing force and the axial extrusion force upon the same location cause a portion of the feedstock material to plasticize, the scroll face further comprising at least one groove and a portal defined within the scroll face, and
a die bearing surface where the plasticized material is recombined, wherein the groove is configured to direct flow of plasticized feedstock material through the portal to a second location on the die bearing surface wherein the plasticized feedstock material recombines at the die bearing surface after passage through the scroll face to form an extruded material having preselected features.