Produce components quicker


Rapid.Tech trade fair in Erfurt highlights the enormous potential of “Additive Manufacturing”

To achieve an innovative product’s form and function quicker, immediate availability through the direct manufacturing of models, components and unique products is of paramount importance, alongside reducing development times. Rapid manufacturing offers the crucial advantage of accelerating the launch onto the market. Rapid.Tech 2010 in Erfurt granted an insight into the current development status. The combination of trade fair, users’ conference and design engineers’ day in cooperation with the “Dental Technology” and “Medical Technology” trade congresses lent an added dynamic to the interest in this key technology.

“Generative processes allow for huge acceleration from the development process through to production”, explains Prof. Andreas Gebhard, the Chair of Manufacturing Technology High-performance Processes at the University of Applied Sciences in Aachen. The use of “Additive Manufacturing“, in the meantime the recognised generic term, is still reserved for progressive companies in Germany, however the technology has grown up and reached industrial standards. The possibilities of generative processes are being used in development and increasingly in production.
Individuality is one of the major trends. As a result, design often decides success on the market. It is essential to immediately understand what a product will look like using prototypes. In an era of decreasing product life cycles, anyone who has to first of all build moulds and tools after virtual realisation, has already thrown away most of its advantage against the competition. “Anyone who is smart, drastically reduces the time up to the first sample and then also directly manufactures using this data”, Prof. Gebhardt points the way. Cost-efficiency plays a major part in modern manufacturing. “Numerous examples prove that additive manufacturing can also be economically attractive”, explain the experts for generative processes. In addition, this technology revolutionises entire industries, for example dental technology, thanks to individualised production.
Even the most complicated moulds with spiral shaped hollow ducts and undercuts can in future be manufactured in one piece in both metal and plastic. As tools and moulds become superfluous, costs sink and manufacturing is sped up. “What is crucial is the benefit that individual customised manufacturing can be combined with industrial production“, emphasises Prof. Gebhardt. Ongoing standardisation reflects increasing distribution, as has happened alongside the VDI guideline 3404 in the USA with the definition “additive manufacturing”.
Enormous progress with materials has silenced the initial criticism of fragile components and inadequate surface qualities. Although the range of materials for “additive manufacturing” is somewhat limited, it is constantly growing.
Whilst the range of standard materials is available, materials for specialist applications must be approved and often also certified. In the process, parameters such as susceptibility to cracking, micropores and thermal resistance play a part. Whilst for example, finishing and surface treatment demand extra work with metal, with high-performance plastics the material itself produces material for research.
Although there are many years of experience with plastics in production, there is still a lack of universal fields of application with rapid processes. “A bit like with print cartridges, the user is tied to the machine manufacturer”, explains Prof. Thomas Seul from the University of Applied Sciences in Schmalkalden. The problem with this is the machine manufacturer might understand the process, but is not usually an expert on materials research. Up to now, processes were largely adapted to existing materials available on the market from other applications. What does customised RM material have to look like? This research area will become more important in future to satisfy the more robust new technology, also in the field of quality control.
A huge change in the modern processing of plastics looms with the introduction of rapid manufacturing. Prof. Seul is calling for an overarching engineering application for the products and applications of tomorrow: “In ten years time 80 percent of turnover will be generated by materials unknown to us today”, he declares. Therefore we must immediately start the search for the materials of tomorrow and drive forward the technology to process them.
Sequential manufacturing processes are not just restricted to plastics, as proved by Dr. Ralf Hoffmann, BMW Group, at the BMW Vision Efficient Dynamics concept car. The free shape combined with additional functions is only made possible by the use of “additive manufacturing”. Hybrid vehicles and lightweight construction rely on these new manufacturing processes. At the same time it becomes clear that it is much more than just the development of moulds and tools: the whole of engineering is challenged by another way of thinking.
Innovation boom in dental technology
Dental technology is one of the outstanding winners due to rapid technology. Dental technicians feel compelled to assert themselves on the market using modern technology, as this branch of industry has experienced an innovation boom in the last three years which other industries would need two decades for, as explained by Antonius Köster, Managing Director of Antonius Köster GmbH & Co. KG. Work without CAD/CAM software hardly seems possible anymore, although it is not easy to find the right solution. Rapid technology plays to its strengths with individualised products like teeth or dentures. A laser sinter plant produces more than 500 dental crowns a day, whilst a dental technician would only manage about two percent of that with traditional casting technology.
The digitalisation of data and modern manufacturing changes the dental technician’s occupational field greatly, as emphasised by Andreas Hoffmann, Dentales Service Zentrum GmbH & Co. KG. Generative processes are being used increasingly with veneers. The manufacturing of aesthetic and bio-compatible crowns and bridges at prices which are significantly below current manufacturing costs, is moving into the spotlight. The shift from manual work to CAD supported automated production, in particular demands increased efforts to prepare prospective professionals in their training for these changes.
In future the optical model will be taken in the patient’s mouth. Changes go deep with the use of systems with intraoral digitalisation, a so called intraoral camera. It is no longer necessary to make moulds at the dentist. After digitalisation in the patient’s mouth the recorded data is reworked using suitable CAD software. The digital image is forwarded to an external processing centre by data transfer. There, specially qualified technicians operate the CNC machines or laser systems for generative techniques. Without having to manually produce a model it can proceed seamlessly to rapid manufacturing. From a technical point of view, the automated processes on the grinding and milling machines, sinter plants, plotters and stereo-lithographic systems merely require qualified machine operators, plus essential requirements which are generally expected of medical products. By 2020, 80% of dental technology work will be carried out digitally, forecasts Dr. Joseph Rothaut, Managing Director of imes-icore GmbH.
Customised implants for surgeons
Medical technology has adopted pioneering generative manufacturing processes, as explained by Prof. Hans-Florian Zeilhofer, Oral and Maxillofacial Surgery at the University Hospital of Basel. “Additive Manufacturing“ allows for the rapid manufacturing of unique products, precisely adapted to the patient’s anatomical features. Models and implants as individualised products reduce costs and improve quality.
Implants manufactured for an individual case make the work for doctors more comfortable and after a more tolerable operation, frequently allow the patient to live a life without pain. Doctors are banking on pioneering innovations in the conflicting areas of three-dimensional planning, virtual reality and the robot supported operation. Prof. Zeilhofer, who is one of the first users of rapid technology in medicine, also sees a really big support through the development of bio-materials, which enable the generation of skin (tissue engineering) and bones (bone engineering).
As surgery methods are undergoing a rapid change, the surgeon constantly needs new instruments, even manufactured specifically for each individual. Aesculap adopts 400 new products into its range every year. Their development time from idea to production consequently has to get shorter and shorter. As a result, tool building has become associated with prototype building and concurrent engineering has been introduced at providers of medical technology. Last but not least, only broad and cross-specialism collaboration leads to success, emphasises Hans Keller, Head of Development, Manufacturing Technology at Aesculap AG & Co. KG. The different processes must be pooled together. “Additive Manufacturing” starts with rapid development to keep development times as short as possible.
One innovation is the manufacturing of a forging die part using rapid manufacturing. The manufacturing of forming tools has not been explored very much but is definitely sensible under certain circumstances, as Dr. Bernhard Müller, Fraunhofer Institute for Machine Tools and Forming Technology IWU, Chemnitz, reports. Typical forging with complex geometry has been produced using a generatively manufactured forging die. The generative process chain is used from the 3D CAD tool construction to process simulation, the laser smelting of die inserts to the actual forging, in order to research benefits and features compared to the usual approach under similar production conditions.
In an increasing number of application fields, only unique products are required with components and even with small quantities generative manufacturing can play to its strengths. Rapid technology is particularly attractive for design engineers because they can continue to develop and use components completely differently. This opens up market opportunities in many areas of use.
Individualisation with component manufacturing is of great interest in water sports. Although the problem is generally unique, sequential manufacturing processes allow for the realisation of complex single pieces. Boat fittings which were manufactured using SLS technology, passed the practical test of a sailing season under the influence of moisture and UV radiation with flying colours.
Architects and structural engineers are using the revolutionary change for functional construction methods. The use of generative manufacturing technology allows for digital planning and the precise adaptation to construction details in the future, explains Holger Strauß, Detmolder School for Architecture and Interior Architecture at the University of Applied Sciences Eastern Westphalia-Lippe. Structures will become possible which were not practical with conventional construction methods. This changes architects’ perspectives: they can downplay the traditional way of thinking, shaped by construction and structure and instead focus on function and character.
Dr.-Ing. Sabine Roth-Koch from the Fraunhofer Institute for Production Technology and Automation IPA, Stuttgart, brings to our attention that often the creative freedom gained through “Additive Manufacturing” remains unused as a result of gaps in the process chain. With the aid of its own developed software, which is now available as a pilot model, it is supposed to be easy to convert design sketches on paper into 3D models, so that product developers can work faster and more effectively.
Bionics use structures from nature to manufacture more efficient products. With the aid of generative technology, components can be recreated based on natural shapes or biology’s construction methods can be used. Where classic processes reach their limits, rapid technology overcomes technical limitations. To support design engineers there is a catalogue which contains solution proposals for bionic and laser generated structures.

Info box
Rapid Prototyping – Additive Manufacturing
Originally the term Rapid Prototyping described the rapid manufacturing of sample components from digital construction data. Today, under the generic term of “Additive Manufacturing”, a method for the rapid production of parts is understood, with which the function or design of a planned application can be tested and optimised early on. Materials and processes already allow today the direct manufacturing of products as single pieces or in small series.

Rapid.Tech 2011
The eighth Rapid.Tech trade fair on 24th and 25th May 2011 in Erfurt will present the latest developments in generative manufacturing processes. Plant and system manufacturers, research institutes, service providers, developers and users will closely cooperate and network at this practical exchange platform on everything to do with “Additive Manufacturing“. The combination of practical trade fair, users’ conference and design engineers’ day gives a unique insight into rapid manufacturing. The “Dental Technology” and “Medical Technology” congresses organised in parallel allow for an open and lively exchange with user industries.