Highly Decorated Hybrid Lightweight Design Metahybrids - When Hybrids Become Even Better
Metahybrids are hybrid parts developed by Automoteam. They feature a special structure and functional properties that were awarded the Industriepreis 2018. This development is said to be a world first.
Conventional plastic-metal hybrid components combine the strengths of plastic and solid metals such as steel or aluminum. They enable the realization of simple hybrid structures that would not be possible with a single material.
Logically, however, such hybrid components also combine the weaknesses of individual materials. For example, in a hybrid component exposed to wear, the metal component must be made of steel and not aluminum. If the hybrid component is to exhibit dielectric properties, the metal component must be completely encapsulated by the plastic and cannot be exposed to wear. This restricts the use of conventional hybrid components in modern applications requiring multifunctionality.
Leading the Way in Terms of Functionalized Material Properties
The new metahybrid technological ecosystem, however, allows polymers and light metals with novel, isotropic and application-specific open-pore or selectively porous structures and/or application-specific modified surface properties to be combined in order to form a unique material system.
Metahybrid components create additional degrees of design freedom as well as new structural and multifunctional properties for material substitution and functional integration. They also impress in applications with conflicting and/or extreme demands on material properties. The multi-stage combination of new process and material properties allows the production not only of conventional material hybrids, but also of higher-level material hybrids - so-called metahybrids.
Surface Layer with a Flexible Optimization Effect
By taking into account new technological possibilities in product development, many new, previously inconceivable potentials are emerging in the areas of multifunctionality, load-bearing capacity, joinability, material compatibility, weight, installation space, resource consumption and economic efficiency of products in all key industries.
The functional weaknesses of light metals in multi-material applications can be optimized by functionalizing their surfaces in the Metaker-Surface process.
Conventionally manufactured or 3D-printed light metal components, as well as water-resistant material hybrids with a light metal component, obtain a novel surface layer with a thickness of up to 200 μm using the economical and very environmentally friendly Metaker-Surface technology. This layer is heterogeneous, graded, multifunctional, microstructured, microporous and atomically adhesive. A Metaker layer is a micro composite material whose properties can be adjusted and combined. Here are some examples:
- Heat conducting, microstructured and abrasion resistant (tribology);
- dielectric and heat conducting (electrical cooling, thermoelectrics);
- electrically conductive and abrasion-resistant (electrical contacts, EMC shielding);
- heat conducting, corrosion resistant and light reflecting (LED, IR measuring instruments);
- atomically adhering to the substrate, microstructured and activated (gluing, laminating);
- body-compatible, microstructured and bioactivated (medicine).
For example, a 99.5% aluminum sheet modified with the Metaker method has a surface microhardness of over 1000 HV, a dielectric strength of 22 kV/mm and a thermal conductivity of 210 W/mK.
A Car Rim Made of Magnesium Becomes More Robust
Not only aluminum, but also magnesium can be treated in the Metaker-Surface process. A striking example of this is a car rim made of magnesium. After its Metaker functionalization, which takes place in one working step without pre- and post-treatment and without the use of harmful substances, the rim is extremely resistant to corrosion and stone chipping and can also be painted with a durable finish.
In many applications, new property profiles of light metals allow the pollutant-free substitution of heavy or expensive materials such as steel, stainless steel, ceramics, brass, bronze, PEEK or complex surface processes such as phosphating, chrome plating, chemical nickel and others.
Double-Digit Percentage Opportunities for Improvement
The special Metaker surfaces increase the performance of light metal components and material hybrids with regard to mechanical, electrical, mechatronic, thermal, chemical, optical, decorative and other applications to a previously unattainable level. Optimization potentials in terms of weight, function, service life, efficiency, resource consumption as well as product and process costs are in the multi-digit percentage range.
Sodium Chloride Makes the Better Pore
Open-pore Light Metals are produced by gravity die-casting with lost placeholders from common salt and are far superior to the well-known metal foam and sintering processes. This includes the application-specific adjustable pore size, the serially reproducible isotropic porosity, the high stability of the cast structure, the possibility of producing almost any conceivable shape by conventional metalworking and conventional surface treatment.
Parameters Determining the Properties of Open-Pore Castings
Open-pored light metal castings eliminate the boundaries between solid light metals and light metal foams. They open up numerous new mechanical, acoustic, thermal, electrical, structural, decorative and many other applications. The structural properties of open-pore castings can be predetermined by a variety of parameters:
- The size of the grain of salt: from a few micrometers to a few centimeters;
- The shape of the grain of salt: Natural stone chunks, round polished salt, shaped salt, etc.;
- Mixed or graded salt grain mixtures;
- Fill level of the mold with salt: Partial filling ensures a partially porous component;
- Use of application-specific molds;
- Use of inserts made of aluminum, steel, glass, copper, etc.;
- Variability in some parameters of a casting process;
- conventional machining and surface treatment of the porous component;
- Production of selective partially porous light metal parts;
- Production of material hybrids from partially porous light metals and other materials;
- Functionalization of light metal surfaces in the Metaker-surface process;
- Use of conventional joining techniques such as assembly, screwing, pressing, riveting, gluing, soldering in both solid and porous component areas.
Numerous Application Possibilities
Even in its standard version, the new material offers great potential for many different applications: Filtering, damping, separating, distributing, regulating, throttling, conveying, flame arresting or protecting, especially as a lighter, better and cheaper alternative to sintered bronze or sintered steel.
Open-pored light metals enable completely new application possibilities thanks to their special properties for function-integrated lightweight construction, multifunctional material hybrids, integrated multifunctional crash elements, integrated heat exchangers, energy and heat accumulators, tools for thermoforming and particle foams, decorative products and much more. The independent, top-class jury of the Industry Award 2018 honored Metahybrid as a best-of solution in the category "Research & Development".
This article was first published by MM Maschinenmarkt.
Original by Peter Königsreuther / Translation by Alexander Stark