Holistic approach: Consistent quality assurance from preliminary product to the EOS laser sintering material
EOS, the global technology and quality leader for high-end Additive Manufacturing (AM) solutions, offers a quality management system that is unrivalled in the industry. It comprises all technological elements from material, system and process that have a direct impact on the quality characteristics of components made with additive manufacturing. Torsten Schlichtholz, Director Global Quality Management at EOS: “By coordinating and controlling all relevant variables, EOS ensures the best possible component characteristics, as such addressing a key concern of our growing industrial customer base, which uses our technology for the series production of plastic components with consistent component quality.”
Materials are one of the supporting pillars of component quality. Under a multi-dimensional quality management system, EOS works with its partners to ensure that each material batch has the same reliable and uniform consistency. Quality assurance already starts with the manufacture of the preliminary product for the EOS laser sintering material. The manufacturing process with all qualification steps is continuously documented and verifiable to the point when the EOS material is delivered to our customers.
For the manufacture of the basic product for the most frequently used plastic Polyamide 12, EOS has been working closely with Evonik Industries for many years where the starting material is subjected to extensive and documented quality assurance procedures even before it is delivered to EOS under a certified QMS (ISO 9001:2008). This comprises all relevant inspections of polymer and powder indicators, such as free-flowing properties, powder density, melt and cooling behaviour and process suitability tests.
The refining process for achieving best possible process suitability is performed on EOS equipment at KVS GmbH (part of EOS) after inspection of the acceptance test certificate/an additional incoming goods inspection. KVS is also operating a certified QM system (ISO 9001:2008) and which defined quality assurance activities are carried out during and after the finishing process. If all criteria are met, a test report is prepared pursuant to ISO 10204.
In addition to the testing of the material itself, specimen and tie bars are manufactured on EOS laser sintering systems based on a reference build job, and their characteristics profile is assessed using acceptance criteria. Products are only shipped to the customer once a batch has passed both test instances. The corresponding test report (in accordance with European and international standard EN 10204 3.1) is attached to each delivery, documenting the relevant test results to the customer, as such providing him with a comprehensive documentation for his own quality management system.
EOS system: reliable compliance to production standards
Since 1998, EOS GmbH has had a certified AM system (ISO 9001:2008) for the development, manufacture, distribution and servicing of systems, materials and solutions for AM using laser sintering technology. Besides the materials, EOS systems form another important pillar for reproducible and exacting component quality. They are also subjected to numerous quality assurance measures, which are inspected and documented in line with the EOS machine acceptance process, during which the defined reference build jobs are prepared and subsequently checked for authoritative criteria such as mechanical properties and dimensional accuracy.
EOS process: tested and warranted parameters
The build process using the appropriate EOS parameter set forms another important element for securing uniform component quality. EOS has more than 20 years of experience in the development and improvement of process products. Standardised parameter sets are created during the material development process, which guarantee robust build processes at our customers and lead to the familiar high component qualities. During the development of the most-often used parameter sets, three build jobs are always performed on three laser sintering systems with three powder batches, in order to ensure consistent part quality at the customer in all conditions.