Exploitable results Repair of aluminium moulds: easy transportable environmental friendly repair process for aluminium moulds and development of new coatings on aluminium Portable repair techniques were evaluated separately for (resin transfer moulds) RTM moulds and injection moulds. For RTM moulds, it was found that thermal spray techniques were suited to the repair of defects with depths below 0.3 mm. Dependent on the deposition material and the (thermal) loads thereon this may go up to 1mm. In particular arc wire spray is highly transportable. A large variety of coatings can be deposited like as done: Aluminium alloys, 316L and NiCrBSi. Aluminium alloys are thermal sprayed on the Aluminium moulds to repair the substrate Aluminium. Whereas 316L steel and NiCrBSi are sprayed and used for repair as protective coatings on Aluminium moulds and moulds made of other materials. Potential applications are expected not only in the plastic manufacturing industry but also for any repair issue on components and industrial commodities. EADS has deposited successfully anti-sticking coatings that will allow a better wear resistance and / or demoulding of the moulded plastic part in particular epoxy resins. Such coatings were prepared by plasma assisted chemical vapour deposition (vacuum deposition). Such type of coatings are used also as hydrophobic coatings, to repel water and dirt from any kind of surfaces. Graining and structuring the surface of an Aluminium mould was carried out by transferring the structure in a electrodeposited Nickel (electroformed Nickel). Regular triangular structures with aspects of a few 10 micrometers were engraved in Nickel. The Nickel was fastened to the Aluminium mould thus forming its surface. Potential application of this technology are already in use when optical and plastic surfaces are structured in the range of less than one micro-meter, like optical grids. Optimised conventional processing and compositions of aluminium plates as well as a new processing route for thick high strength aluminium plates ALCAN has developed special alloy with high yield strength and design methodology for aluminium moulds. Optimised conventional processing and compositions of aluminium plates specifically dedicated to the mould industry were developed. Their yield strength amounts to 500 MPa at a thickness of a 500 mm plate. Furthermore, new processing route for thick high strength aluminium plates specifically dedicated to the mould industry with a yield strength of 600 MPa for a 1000 mm plate with very low through-thickness variations were developed. Surface hardening for aluminium moulds: optimised coating process for surface hardening of aluminium alloys An optimised coating process for surface hardening of aluminium alloys was developed with the following parameters: thickness: 100µm (partline), 10 µm (cavity), hardness: < 2500 HV (partline), 2500 HV (cavity). Surface treatments on the aluminium moulds have to be deposited below 150 °C in order to preserve the mechanical properties of the alloy. Those surface treatments provide: - a surface hardening that protect the mould against wear occurring on the movable parts during the demoulding operations; - anti-sticking properties that will allow a better demoulding of the moulded part. Two types of surface treatments were considered: conventional treatments (electroless Ni for example), and PVD / PACVD treatment that have been developed to be specifically applied on aluminium alloys. Achieved results: - A cleaning procedure, specifically designed for aluminium, has been defined. This procedure allows a cleaning prior the PVD / PACVD surface treatment that not corrode the aluminium surface and offer a good degreasing before beginning the vacuum treatment; - Three PVD / PACVD coatings have been developed. Cr2N, CrN and DLC have been deposited with process temperature below 150 °C. The hardness is around 2 000 kg / mm2 for the two chromium nitride coatings and more than 2 500 kg / mm2 for the DLC coating. The thickness is comprised between 1 and 3 µm depending on the coating. A combination of DLC deposited on chromium nitride (in the same batch) has also been developed to improve the load bearing capacity of DLC. The new PVD / PACVD processes can be applied to all kind of aluminium alloys parts and can also concern applications different from moulding. Graining process for aluminium moulds: optimised graining process for aluminium alloys: depth: 0.1-0.2 mm Work conducted within the ALUMOPLA project allowed MOLDTECH to gain experience in graining aluminium moulds, especially by developing new chemical baths combining a good result regarding pattern aspect, as well as a process with a suitable etching rate. The injection prototype tool engraved by MOLDTECH, despite not engraved with the latest graining bath, allowed to check the quality of the grain on aluminium tools. Searching for OpenAIRE data... There was an error trying to search data from OpenAIRE No results available
