When last we looked in on the Rapid Solidification Process for advanced tooling alloys for molds and dies (see FM&T October 2004, p.20), the system had been awarded its fourth patent and had made the move from research lab to commercial introduction. A year later, that research continues on some specific details at the Idaho National Laboratories, on assignment from the Dept. of Energy. More important to manufacturers, RSP Tooling L.L.C. has been guiding the process into the real world of moldmaking — including diecasting molds.
RSP started as a DOE research program to improve the performance capabilities of mold and die materials in order to increase die life by at least 20%; and to reduce energy consumed in manufacturing and heat-treating dies by at least 25%. As carried out by a development program at the Idaho National Laboratory, the strategy was to develop and demonstrate a new class of mold-and-die tool steels tailored for spray forming. Finally, once the equipment capable of this rapid solidification process (RSP) was successful, it was licensed to a company established for the purpose, RSP Tooling.
RSP Tooling, Solon, OH, now operates a "beta" machine that was custom-designed and built by Belcan Corp. Over the past year it has been producing commercial-quality tooling for forgers, diecasters, extruders, glassmakers, and other manufacturers, with some notable success.
Working from CAD models supplied by customers, RSP Tooling uses stereolithography to create the tools in plastic. From these shapes, ceramic models of molds are made, and these become the forms on which metal is spray-deposited to create final tools.
Virtually any tooling alloy can be used, though RSP Tooling president Jim Knirsch observes that H13 results in a better hardness standard than any other material. Metal is atomized down to drops as small as 5 microns, which speeds its solidification, and then it is deposited onto the form. The complexity of the tooling does not significantly influence the cost of production, which should be a significant selling point to diecasters.
Moreover, the process is repeatable and RSP Tooling reports the cost for additional inserts is about 50% of the cost of the initial one, making it particularly well-suited for producing multi-cavity dies and replacement inserts.
While the commercial effort to date has involved manufacturing dies, Knirsch explains that the company’s plan is to sell entire production packages so that customers will design and produce their own dies.
As explained by Knirsch, most of the firm’s early progress has been made producing forging dies. The Forging Defense Manufacturing Consortium has supported their foray into that market and so far RSP Tooling has supplied seven forging companies with dies, demonstrating immediate commercial impact. Knirsch notes that their success in this segment is partly due to the fact that forging tools have no complex shapes, so they can be produced quickly, and by the fact that forgers have comparatively low expectations for tooling life. From their perspective, any improvement is a significant saving in tooling costs.
But, diecasters are also getting the message. Three diecasting organizations have contracted RSP Tooling for prototype molds, and so far there is one notable success, according to Jim Knirsch. After receiving the CAD drawing of the die, RSP Tooling was able to deliver a mold used to diecast an aluminum automotive part. He adds that they are also working on mold designs for electronic parts. For operations that typically cast in sand or plaster molds, these new molds are vast improvement. They become cost-effective after yielding 30 parts, according to Knirsch.
Some projects may be limited by size. As of now RSP Tooling’s production capability has a maximum size of 7 in 2, or 5 in 2 for the finished part. Also, it cannot produce core designs, though many diecasters will use inserts in any case, Knirsch says. On the other hand, these items can be produced in as little as two hours, in an affordable and reliable way.
He regards the diecasting market as one with the greatest growth potential, and expresses confidence that more documented results will bear out that confidence.