RSP Tooling Background and History
Dr. Kevin McHugh The INEEL Spray Chamber
The Rapid Solidification Process (RSP) was developed at the Idaho National Engineering and Environmental Laboratory (INEEL) under grants from the U. S. Department of Energy. The initial patent for the process was written in 1990 and had as its basis the invention or discovery that a liquid could be broken down into small droplets by use of the shearing effect of a flowing gas. There are a large number of possible applications of this invention.
An early application was the production of low-carbon steel strip, the industry’s highest volume commodity. There are many advantages to producing strip by using RSP, with the most important from the point of view of the DOE being a significant reduction in energy use. It was felt that if strip could be produced directly from the molten metal with enough accuracy, hot rolling unit operations could be eliminated, saving time, money and energy.
Work on the process resulted in another patent in 1995 which introduced the use of pressurized injection of liquid into a Ventura tube, thereby improving the operational flexibility of the device while producing a more uniform droplet size distribution in the spray. An additional benefit was the ability to control and increase the cooling rate of the droplets (thus the name), which results in microstructure and material property improvements in the deposited metal.
Since the grain structure of the spray deposited metal was good, as was the ability of the spray deposited metal to replicate complex surface shapes, the idea of using the process to manufacture tools was developed. This resulted in a new patent in 1997, and in the terminology of RSP Tooling. Additional patent applications have been submitted which refine the actual process to produce tooling.In 1998 Kevin McHugh won a R&D 100 award for a valuable invention. This resulted in the decision to license and commercialize the process.
