Accumulative Roll Bonding of Ultrahigh Strength Light Alloys

The proposed Phase I SBIR project will conduct exploratory development of scalable manufacturing processes for producing high strength lightweight metals. This Phase I SBIR program will extend work and significant prior investment that Powdermet has carried out in the nanocomposite and syntactic composite aluminum system, and in this program we will utilize recent developments in nanocrystalline magnesium alloys, along with large scale mill equipment purchased and installed by Powdermet to produce 12"X 12"plates using a series of processing schemes. The base approach to be taken in this Phase I program will be to try and validate the exploratory work done on milled, Mg-2Y-1Zn alloys by Koch et al, which demonstrated over 2GPa hardnesses in mechanically alloyed Mg-2Y-1Zn alloys that were hot pressed at 180 degrees C to develop long range order. The long period superlattice phase proposed by Inoue in rapidly solidified Mg-Y-Zn alloy powders, combined with the nanocrystalline grains size derived from the mechanical alloying process at North Carolina State University, are believed to be the underlying strengthening mechanisms resulting in the high strength. This program will focus entirely on the magnesium alloys during Phase I.