Further Investigations in Low-Pressure Close-Coupled Gas Atomization

摘要

Atomization of molten metal by close-coupled atomization technology generally requires the use of high-pressure gas (2.5 MPa and higher). There are numerous powder production applications that operate in large batch or continuous mode (Al, Sn, Zn, and Pb) where the delivery of gas at these pressures is not desirable due to economic or hardware constraints. This impedes the use of close-coupled atomization technology for these existing production atomization applications. A previous study showed potential for the use of lower gas pressures (1.7 MPa) as applied to close-coupled atomization. This study investigates a pressure regime lower than previously investigated; 0.1 to 0.7 MPa. This work entails an engineering study of the attributes of low-pressure gas atomization. The flow parameters of a typical close-coupled gas atomization nozzle operating at low pressures will be characterized with the use of a gas/water flow bench. Atomization tests using several commercially important alloys will be performed to test the performance of the atomization in the low-pressure regime and to determine other attributes of low-pressure gas atomization.