Nozzle clogging in vacuum induction melting gas atomisation: influence of gas pressure and melt orifice diameter coupling

Abstract

The clogging problem of close-coupled nozzles in the vacuum induction melting gas atomisation (VIGA) process is studied by numerical simulation and industrial experiments. To understand the factors affecting lick back on the nozzle, volume of fluid (VOF) multiphase flow model simulation was adopted to visualise the motion of alloy melt around the outer wall of the delivery tube in the primary atomisation process. When the melt orifice diameter is 4 mm and the atomisation pressure is close to 3.5 MPa, the atomisation process is continuous, the powder particle size is fine, and the atomiser can be reused. When the orifice diameter is 5 mm, and the atomisation pressure is greater than 2.5 MPa, the risk of nozzle clogging is avoided, the powder size is relatively coarse. In the case of using the same atomiser structure, this study explains the mechanism of lick-back and the resulting nozzle damage in VIGA units.

An overview of additively manufactured metal matrix composites: preparation, performance, and challenge

“…As reviewed, many metals and alloys can be used as the metal matrix to produce MMCs, such as Al, Ti, Ni Fe, Co, and their alloys. The widely used methods for producing metal matrix powder are gas atomization [180], electrode induction melting gas atomization [181], vacuum induction melting gas atomization [182], plasma atomization [183], water atomization [184], centrifugal atomization [185], and plasma rotating electrode process [186]. Irrespective of the powder production methods, there is a widely acknowledged consensus that the cost of powder employed in the AM process is high [71].…”