Novel Manufacturing of Bulk Metallic Glasses

Materials and Manufacturing Systems, Inc. (MATSYS) proposes to develop a novel manufacturing technique for greatly increasing fine powder yield and improving particle size control by significantly increasing the supersonic gas jet length downstream of the nozzle tip to increase the length of the breakup region and maximize the breakup of the powder. This objective can be achieved by control of the atomizer chamber pressure. Typical controlled-atmosphere atomizers operate with chambers at or slightly above atmospheric pressure. However, if one drops the chamber pressure below atmospheric, one can effectively increase the expansion ratio of the atomizing gas, which produces slightly higher gas velocities and significantly longer supersonic gas jet lengths. The elongated jet lengths will improve atomization performance in the region well downstream of the nozzle, leading to the sought after high yields of fine particles. The ability to control the chamber pressure is the key factor that enables us to examine this previously unexplored processing space. During this program, we will atomize metallic glass compositions, characterize the interaction between chamber pressure and other key atomization parameters, develop the control system to control fine powder yield and particle size, and scale-up the process for cost-effective, high volume production.