IMFLUX, Procter & Gamble’s recently established mold design and manufacturing business, is expected to focus on tools made from aluminum alloys, which can be made with simplified cooling systems.
The result will be molds that are not only less expensive, but also capable of producing more consistent, high-quality parts. The focus will be on the types of thin-walled parts such as those used in packages for consumer products such as cosmetics. Medical parts are also a target.
The aluminum alloys specifically under investigation are QC-10 from Alcoa (Pittsburgh), Duramold-5 from Vista Metals (Fontana, California), and Hokotol from Aleris International (Beachwood, Ohio). The alloys are more easily machinable than tool steel and also have better thermal conductivity, meaning that heat can be transferred more easily into coolant.
Cooling channels milled 5 mm from the mold cavity with the aluminum alloys reduced the temperature delta by as much as 78 percent compared to similarly placed channels in tool steels.
In some cases, cooling systems can be located in mold support plates, allowing molds to be changed without changing cooling systems. Detailed descriptions of the simplified cooling systems in side plates are outlined in U.S. Patent Number 9,089,998, which was recently awarded.
One significant benefit of the system, is that the temperature profile of the mold is more uniform, resulting in less internal part stress and a more uniform crystalline structure, according to inventor (and iMFLUX chief) Gene Altonen. The payoff is reduced warp, a very significant consideration for parts with high length versus thickness (L/T).
The benefits of aluminum alloys as mold materials have been well documented, but what’s different now is that the iMFLUX molding process operates at low pressures that permit their use in more demanding, high-volume applications.
Traditional injection molding machines for thin-walled parts operate at pressures typically greater than 15,000 psi so that thermoplastic is fully injected before it can freeze off. In the iMFLUX invention, the injection pressure is less than 6,000 psi. The benefits are numerous, both in equipment and mold cost savings as well as part quality. Even optical properties of skin layers are said to be improved.
The technology is based on very careful pressure control.
The number of employees at iMFLUX, which was founded in 2013, is nearing 100. The plan is 250 employees in two years. To date, the company has filed for more than 30 patents and seven have been granted.