The UltraPLAS coating newly developed by Fraunhofer researchers solves various problems in forming processes. The release and easy-to-clean coating is applied as a gradient layer using a cold plasma process and is suitable for materials such as tool steel, stainless steel and aluminum. The physical properties of UltraPLAS ensure a perfect reproduction of nanoscale to mirror-gloss surfaces. As its use reduces the number of post-processing steps and eliminates the need for external release agents, the application is considered to be particularly cost-effective.
GlossyCast and UltraTrenn research projects
The aim of the IGF-funded "GlossyCast" and "UltraTrenn" projects was to reduce the demoulding forces and the formation of deposits on the mould surfaces while permanently withstanding the specific stresses of zinc die casting and plastic injection moulding. Researchers from the Fraunhofer Institute for Manufacturing Technology and Advanced Materials IFAM worked together with partners on UltraPLAS.
Outstanding coating properties
In order to create a release coating with an ultra-smooth, optical surface (Ra < 25 nm), the coating itself must be smooth and structureless. The cold plasma process enables high layer adhesion to the product body on the one hand and good non-stick properties on the product side on the other. The coating produced in this way is characterized by a high modulus of elasticity (28 - 32 GPa) and a high density (1.5 g/cm³). The Mohs hardness range of 5.5 is on a par with glass or enamel. The surface energy of < 28 mN/m is low, as is the polarity of < 1.5 mN/m. The cold plasma process also enables particularly thin layer thicknesses of less than 100 nm.
Sustainable quality and economical production
Practical tests have shown that demolding forces and coating formation can be reduced in the area of injection moulding. By reducing the adhesion forces, the demolding forces decreased overall. As a result, the demolding temperature can be increased and the amount of friction reduced. In contrast to the state of the art, the coating can be removed effectively and gently using plasma technology so that, if necessary, a new coating can be applied several times without any loss of quality. This is particularly interesting for high-gloss tool surfaces, as it eliminates the need for time-consuming polishing or ultra-precision machining.