Laser-Sintering Powders Target Aerospace Industry

Two powdered metals for the rapid manufacture of nickel alloy and aluminium alloy components by additive layer manufacturing have been introduced by EOS Electro Optical Systems. The company has specified the materials for use in its EOSINT M 270 laser-sintering systems. EOS nickel alloy IN718 is a nickel-based, heat-resistant super alloy, which corresponds to Inconel 718. It is a precipitation hardening, nickel chromium alloy characterised by good tensile, fatigue, creep and rupture strengths at temperatures up to 700C.

It shows high corrosion resistance, is suitable for many high-temperature applications and possesses strong cryogenic properties. The material may be of particular interest to the aerospace industry due to its demanding requirements. EOS said that it has carried out extensive tests in collaboration with several pilot customers. It has developed process parameters that enable good part building and ensure that the relevant industrial standards for this material type can be reliably fulfilled.

These include, for example, heat treatment in accordance with AMS 5662 and AMS 5664 standards, as well as tensile and stress rupture properties at elevated temperatures (650C). EOS aluminium AlSi10Mg powder, a typical casting alloy, is the first aluminium-based powder to be qualified for EOSINT M 270 systems and opens up application areas due to its light weight and thermal conductivity. Thorough process development and testing were performed as preparation for the launch. Cast parts in conventional AlSi10Mg are typically subjected to T6 heat treatment including solution annealing and quenching followed by age hardening at elevated temperatures.

EOS has already produced examples of laser-sintered aluminium alloy components illustrating intelligent designs such as hollow parts and mesh-like structures with high stiffness-to-weight ratios. The material is expected to open up new markets in the area of light alloys.

Euromold To Feature EOS Laser-Sintering Systems

EOS will display its EOSINT P 395 and EOSINT P 760 plastic laser-sintering systems at this year's Euromold exhibition, to be held 2-5 December 2009. The modular nature of both systems allows for a high degree of flexibility. Individual modules can be excluded at first, reducing the initial investment, but can be added at any future time. Both systems also offer the option for upgrading, with substantially improved process modules to support the strategy of part property management. A re-engineered laser-optics module (surface module) improves the quality of vertical surfaces into regions that until now have been exclusive to Formiga parts.

The Eosint P 760 can be optionally equipped with OLPC, which monitors and controls the laser's power during the building process, ensuring a more constant power than was previously possible. The Eosint P 760 is available with Flashrecoating, a new x-axis control that increases productivity by accelerating the re-coating speed up to 400mm/s. With the appropriate packing density, build-up rates of up to 700cm/h are realistically achievable. The recoating unit in the Eosint P395 has also been improved.

The introduction of PPPs has led to the integration into the Eosint P 395 of EOS's successful blade-cartridge concept, which was introduced in the Eosint P 730 in 2007, making it simple to carry out adjustments and change the layer thickness. A new version of the Eostate software, which monitors and reports on laser-sintering production, will also be presented at Euromold. Eostate 1.2, with a new array of report and analysis options, is EOS's answer to the increase in demand for transparency and continuous quality assurance in series-production processes. As such, the software complements the PPPs perfectly and is available for all plastic and metal systems.

The standardised reuse of powder materials is a prerequisite for continuously sustaining high quality in ongoing production. To fulfil this, EOS has adapted the successful concepts of other product lines to develop an integrated process chain management (IPCM) for Eosint M systems. The most important step here in quality assurance is the fast sieving of powder under defined conditions before its reuse. The IPCM ensures vibratory sieving under defined conditions and mesh sizes adapted and optimised for individual powders.

Powder preparation outside the machine, for example via powder homogenisation, enables the highest quality as well as maximum productivity and flexibility. Further increases in productivity and user-friendliness can be achieved with EOS's IPCM modules for fast powder conveying and machine refilling. The IPCM product range includes multipurpose lifting trolleys for transporting powder containers, as well as for building platforms and clamping systems.

Laser Sintering System Produces Dental Implants

EOS's EOSINT M 270 laser-sintering system can manufacture dental implants by direct metal laser sintering (DMLS) using a focused solid-state laser. The Millenium Research Group estimates that the European market for crowns and bridges will grow annually by an average rate of eight per cent until 2012. Technological advancements in the field of dental care are contributing to this by employing production methods such as laser sintering to provide dental restorations, which are more affordable, more readily available and of high quality.

Until now, dental implants have traditionally been made out of metal via a casting process. This process enabled a technician to produce 20 dental frames per day. One automated laser-sintering machine can produce up to 450 parts for dental crowns and bridges within 24 hours, and all of the finished parts will be of the same quality. The tasks of deflasking and cleaning moulds are dispensed with, thus allowing the dental technician to concentrate on a core competence, namely the post-processing of the metal structure and its aesthetic upgrade: ceramic veneering. EOS's EOSINT M 270 laser-sintering system can be used to manufacture dental implants.

The machine uses CAD data to produce, from metal powder and in only a few hours, complex geometries that exhibit excellent mechanical properties, surface quality and detail resolution. The CE-certified EOS Cobaltchrome SP2 alloy was developed by EOS especially for the dental industry for use in the EOSINT M 270. EOS demonstrated the entire process chain at the 33rd International Dental Show (IDS) from 24-28 March 2009 in Cologne. All the steps involved in laser sintering crowns and bridges were shown, from the initial scanner to the creation of the 3D CAD data and the laser-sintering machine, and ending with the finished veneered product.

The further development of dental CAD/CAM applications with new impression and intra-oral scanners will make it possible to send high-quality data directly to the processing centre. The only thing missing would be a dental model for occlusion testing and post-processing, or a workpiece holder for use during veneering. Such a model can be laser sintered on a Formiga P 100 from PA 2200, a quality plastic, on the basis of already available data. Laser sintering provides a complete solution for the manufacture of dental implants.