Rotating disk atomization

This process, originally designated as RSR (rapid solidification rate), was developed by Pratt and Whitney Aircraft Group and first operated in the late 1975 for the production of rapidly solidified nickel-base superalloy powders.[185][186] The major objective of the process is to achieve extremely high cooling rates in the atomized droplets via convective cooling in helium gas jets (dynamic helium quenching effects). Over the past decade, this technique has also been applied to the production of specialty aluminum alloy, steel, copper alloy, beryllium alloy, molybdenum, titanium alloy and sili-cide powders. The reactive metals (molybdenum and titanium) and 

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Rotating Disk Atomization (RSR) -60 Standard deviation 1.4-1.6 Ni-superalloys, Al, Be, Ti, Mo, Cu alloys, Steels, Silicide 105-107 3-18 <0.9 Spherical, clean, smooth particles, Narrow size distribution, High EE Relatively low capacity throughput... 

Electron Beam Rotating Disk Atomization (EBRD) <700 Narrow size distribution Refractory, reactive metals and alloys such asTi >103 -5.5 -0.5 Relatively high EE Coarse (flaky) particles, Relatively low capacity throughput... 

Figure 2.21. Schematic of rotating disk atomization of melt.

This approximate relationship is similar to those for centrifugal atomization of normal liquids in both Direct Droplet and Ligament regimes. However, it is uncertain how accurately the model for K developed for normal liquid atomization could be applied to the estimation of droplet sizes of liquid metals Tombergl486 derived a semi-empirical correlation for rotating disk atomization or REP of liquid metals with the proportionality between the mean droplet size, rotational speed, and electrode or disk diameter similar to the above equation. Tornberg also presented the values of the constants in the correlation for some given operation conditions and material properties. 

In spinning disk atomization, the construction of a rotating disk atonuzer depends on the application and the liquid that will be used. However, the rotating disk atomizer will always require a pump or other device for feeding liquid onto a rotating disk from which the drops will be discharged. 

J. C. Ogbonna, M. Matsumura, T. Yamagata, H. Sakuma, and H. Kataoka. Production of micro-gel beads by a rotating disk atomizer. Journal of Fermentation and Bioengineering, 68(1) 40—48, 1989. 

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