Gas Atomization of Molten Metal: Part II. Applications

Abstract

A numerical model was derived to obtain results for two alloys during the Gas Atomization (GA) method. The model equations and governing equations were implemented through the application of part I data. Aspects such as heat transfer, fluid mechanics, thermodynamics and law of motions were taken into account for the formulation of equations that take gas dynamics, droplet dynamics and energy balance or conservation into consideration. The inputs of the model include: Processing parameters such as the size of the droplets, characteristics of the metal alloy, initial temperature of the molten metal, properties and fractions of the atomization gas and the gas pressure. The outputs include velocity and thermal profiles of the droplet and gas. Velocity profiles illustrate the velocity of both droplet and gas, while thermal profiles illustrate cooling rate and the rate of temperature change of the droplets. The alloys are gamma-Titanium Aluminide (γ-TiAl) and Al-3003-O. These alloys were selected due to the vast amount of applications both can have in several industries. Certain processing parameters were held constant, while others were altered. The main focus of this study was to gain insight into which optimal parameters should be utilized within the GA method for these alloys and to provide insight into the behavior of these alloys.

Recent Advancements in Material Waste Recycling: Conventional, Direct Conversion, and Additive Manufacturing Techniques

“…Generates spherical metal powders which can be used for additive manufacturing [191], higher atomization efficiency, and a greater consistency with the spray [273].…”

“…to metal freezing prematurely within the delivery tube. Pressure can become positive or negative from the gas stream with the nozzle tip, which can cause an increase in metal flow rate or a blockage during actual experimentation [273].…”

Insights into the assessment of spreadability of stainless steel powders in additive manufacturing

“…Size of the droplets and gas composition in the chamber has a significant impact on the cooling rate. Such that smaller droplets at 100% helium produce higher cooling rate and less solidification time since heat transfer is faster in these situations [37]. Particles atomised in lower cooling rate exhibit higher crystalline fraction and on the other hand particle atomised in a higher cooling rate show a higher amorphous fraction [31].Amorphous metals exhibit excellent mechanical properties and have greater wear and corrosion resistance due to the absence of grain boundaries compare to crystalline materials [38][39][40].…”

Sustainable Recovery of Titanium Alloy: From Waste to Feedstock for Additive Manufacturing

“…Nowadays, metal powder for additive manufacturing is mainly produced using the gas atomization technique [187]. The metal is melted by using a vacuum induction furnace operating at high temperatures, and then it is atomized by a high-pressure (between 0.5 and 4 MPa) jet consisting of an inert gas (i.e., argon and nitrogen) [188]. The entire process is energyintensive [189] and produces harmful smoke during the metal melting.…”