Surface structuring optimises material characteristics

For more than 15 years, T. Michel Formenbau GmbH & Co. KG from Lautert in the Taunus has been developing and producing tools and moulds for the plastic-processing industry. The portfolio of the company with its 50 employees ranges from product development, 3D design, 3D digitalisation and prototype construction to the mechanical machining of particle foam, injection mould and deep-drawing tools for mass production. The key fields of application include the automotive branch, the packaging and toy industries and the construction industry.

As T. Michel Formenbau fully understands the complete process development in the field of particle foaming, the company’s knowledge base forms the basis of innovative designs and solutions for many market areas. As a result, it is currently impossible to imagine the automotive world without the benefits of foamed components. The crash behaviour of EPP is used in the manufacture of bumpers, boot inserts and door structures. The insulating properties play a central role in the E-mobility sector. As approximately 45% of the battery energy in an electric car is required for heating the vehicle, appropriate insulation thanks to the use of particle-foamed components leads to a significantly higher vehicle range. The saving in weight with the consistent use of these components internally and externally is approximately 50%. This is also currently leading to a massive rethink by designers and constructors.

The collaboration between T. Michel Formenbau and the vehicle design is constructive and synergetic. The limitation of laser machining due to narrow contours or difficult-to-access structures can be virtually eliminated by defining intelligent parting lines or positioning visual seams and shadow gaps at an early stage. Here, the process knowledge of T. Michel Formenbau comes to bear in the early stages of product development, and the close collaboration between tool maker and design ensures that not only is the product feasible but also a cost reduction of up to 50% is achieved. The increasing importance of these components, particularly in the visible area of the vehicle, and the limitation of particle foaming with regard to colour and UV resistance have led to a new technology of PCIM.

“Particle-foam composite injection moulding” inseparably combines EPP or EPS with thermoplastics such as ABS, PP or TPE. This gives the force-absorbing components in the interior a haptically appealing surface finish and durability. Thanks to considerably increased rigidity and the opportunity for integrating new load-bearing elements, the components also undertake additional fixing and supporting functions.

Revolutionary developments thanks to LASERTEC Shape technology

In 2013, T. Michel Formenbau put into operation the first LASERTEC 125 Shape from DMG MORI and was now able to mill and texture tools in a single setup. Thanks to new micro-texturing, this enabled a revolutionary expansion of the range of particle foaming applications. In this way, it was possible to generate surface structures which provide EPP with waterproof properties by modifying the material beads. The integration of these new surfaces into the market was extremely positive thanks to the systematic provision of information to processers and designers, and led to the machines, which were commissioned in 2013, being fully utilised.

The need to expand capacity, and also the orientation towards larger components, led to the decision to install another Hybrid-Laser-Milling machine LASERTEC 210 Shape from DMG MORI. This was put into operation in March 2016 and, with the improved software, enables considerably more complex structures with corners and sharp-edged elements to be laser-machined. On the machine, workpieces with a maximum clamping area of 2×1.8×1.2 m and a weight of up to 8 t can be mechanically machined and fine-structured with high precision by means of a laser in a single setup.

Research into the future of surface structuring
T. Michel Formenbau is currently setting up a plastics technology centre in order to promote basic research into the integration of foams and injection moulding. The prerequisite for overmoulding particle foam parts is a homogenous EPP surface. Like other functional surfaces, such as soft-touch or anti-squeak surfaces, this is made possible by laser texturing.

The limitless opportunities of surface structuring using the ecologically superior laser texturing technology are also leading to revolutionary changes in other markets and applications. T. Michel Formenbau is making available the whole of its process knowledge and is providing designers and constructors with new ways and strategies of realising components or hybrid materials with integrating properties.

Thermally insulated containers in the foodstuffs industry can be foamed hygienically thanks to the sealing of the porosity by means of the tempering process on the tool surface and the resulting formation of a skin. In the air conditioning industry, it is possible to construct lightweight pipes with insulating and anticorrosive properties. In the heating and ventilation industry, water-repellent components which combine insulating and optical properties can be produced in one part.

In the leisure industry, the development of expanded thermoplastic polyurethane (E-TPU) is revolutionising training shoes. The light-as-a-feather material has performance-increasing rebound effects and is replacing EVA in importance to an ever increasing extent. Here too, design and functional surfaces are realised using laser-textured tools. In the production of therapeutic massage rollers, for example, rotation laser machining enables textures which have no transitions at the bonding points to be incorporated in the development.

The continuous flair for innovation demonstrated by T. Michel Formenbau is supported and made possible by the LASERTEC Shape technology and the high degree of process integration on the DMG MORI machines. The synergetic collaboration between machine manufacturer, service provider and design and construction are visible to all in the advantages for the environment and technology in everyday life as described above.