The sinter is evolving from rapid prototyping to series production

The sintered laser can become the key to open the doors of the manufacturing for measure, also known as e-manufacturing or electronic production. It is a type of flexible production that provides solutions for every stage of the process of manufacture of a product, from development and production to delivery to customers. On the other hand, it adapts both mass product production and small productions aimed at niche markets or trends of season subject to fluctuations in demand. In this line is working the signature EOS (represented in Spain by Protoser), one of the leading specialists in this type of production and whose progress we detail in this article.

The system of high productivity Eosint S 750 uses the DirectCast patented process for manufacturing without mold cavities and males for sand casting. Compared to its predecessor, Eosint S700, it is equipped with powerful lasers and a patented technology of double focus and that now it is used under license in some Stereolithography systems. Two lasers of the Eosint S 750 system scan the internal regions of pieces sintered much faster, thereby increasing production. Dr. Florian Wendt, of ACTech (Freiberg, Germany), development partner and client of EOS explained that this increase may even double the productivity.

PrimeCast 100 to produce models for casting by vacuum

DirectCast is a revolutionary method for the production of pieces of laundry in a very short time. It was developed by EOS GmbH Electro Optical Systems in Munich (Germany). This system uses Laser sintered to make molds, and males to cast iron in sand directly from CAD files, which saves time and money in the development of unique small series or components.

Based on this patented method, model is first designed in CAD, then occurs automatically in a machine of sintered laser, which brings together the grains of sand coated resin layer by layer according to the digital model available machine. Males can be completed within hours and used to produce castings of steel, aluminium or magnesium, to give some examples. Normally, most of casting parts require machining molds, which delayed production at least several weeks.

This technology has introduced the EOS in a sintered laser system called Eosint S 700, using companies in automotive such as BMW, DaimlerChrysler, Ford, ITT Flygt, Nissan, Porsche, and Volkswagen. Eosint S 700 is a system of rapid prototyping - which uses two lasers - which works directly from 3D CAD data. His workload is 720x380x380mm, enough to manufacture components of engines of four and six cylinders in one piece, such as cylinder heads, or a large number of young males at the same time. Typical applications are development of groups motopropulsores, pumps, engines and hydraulic systems.

The system of double laser Eosint P700 is used for sinter laser of plastic parts. The system-"Integrated Process Chain Management (IPCM)" - which includes food and recycling of materials and a system of parts manufactured with interchangeable deposit - clearing offers a high level of automation and ease of use. For the preparation of data, there is a new software called Eospace, developed by Materialise for EOS. Eospace is an application to automatically place the pieces in the volume of construction optimizing its height, that works according to the actual surface of the pieces.

On the other hand, Eosint P 700 ensures the surface quality of pieces sintered by a careful control of temperature. According to a member of the Department of rapid prototyping of the DaimlerChrysler firm, this system, along with the new material PrimerCast 100, is the world of prototyping more productive machine fast.

PrimeCast 100 is a new material made of polystyrene for sintered laser Eosint P systems. This material can be manufactured quickly and cheaply patterns for casting molds by vacuum. They are patterns of high dimensional accuracy and resistance, as well as easy to handle. The surface quality is very good: after an infiltration with resin can be achieved by a surface finish of mirror. This polystyrene can also be used in techniques of wax. Anyway and use as it is used, the material is completely reusable.

This new material has been tested by several companies, such as Alphaform or DaimlerCrhysler, to which we have already referred. The nuremburguesa company FIT (Fruth Innovative /), for example, client of many years of EOS, employed this new material in Eosint P to produce models for a grill directly through the sinter laser, made using the lost-wax method. The plastic of the grill rack was produced by casting by vacuum. Using this direct method, FIT reduced its costs by 29 percent.

The sintered laser can be used without problems in the production of moulds for small series with materials such as bronze and steel of 20 microns, 20 DirectMetal or Direct Steel 20, respectively. They are built with a machine Eosint M 250 Xtend.

In industries such as the manufacture of sports goods, for example, often have have small series that are not profitable if used more conventional methods of production of moulds. These sectors are fertile ground for sintered lasers, which also offers a freedom unknown up to now in the design of these molds. An example is the integration of the cooling channels.

This method was the subject of a joint project between the Italian firm EsTec with Democenter, who got 20 million golf balls series with molds sintered by laser. The pieces were manufactured by extrusion - blown polypropylene, followed by an injection of elastomer. The high number of produced balls may seem astonishing, but channels of cooling following the shape of the piece and the systems of ventilation desaireación in the inserts of the mold - unthinkable in conventional systems - improved critical properties of the mold. This improved levels of production and the sphericity of the balls.

Another example taken from products "in season" - subject to fads and several trends - was the key fob in the shape of scooter for motorcycle, produced in small series of hundreds of pieces. It was a bicolor Keychain injected through a system process. The mold was made using Direct Metal 20 as a material in an Eosint 250 Xtend and the quality was so high that it was not required or polished postmecanizado.

Another example, the TransCat company wanted a mold for the injection of a fan as soon as possible, so used DirectMetal 20 and the Eosint M 250 Xtend and built its mold in 16 hours. After a brief micro-blasting and polishing, the mold was used to inject series of thin-walled parts (PA6 + 30% FV) to work at 30,000 rpm

So were the llaveros-scooter.