Lehvoss: 3D printing materials tested according to EN 45545

The use of plastics in railway vehicles has represented the state of the art for a number of years now. In component production for this field, too, 3D printing is becoming increasingly important, with 3D printed plastics being put to use on both the outside and inside of railway vehicles. Apart from its use in new vehicles, additive manufacturing is also displaying its strengths in the production of spare parts. The required components can be produced cost-effectively in small and medium-size quantities and, in some cases, the reacquisition of parts only becomes possible at all through 3D printing.

Components in railway vehicles are subject to special requirements in terms of their fire characteristics. In Europe the applicable standard is EN 45545, which contains various tests that simulate the behavior of materials in the event of a fire. Among the parameters determined are smoke density and oxygen index. Depending on the field of application, the requirements here are higher than even the strict demands of the aviation industry. Classification is based on hazard levels (HL1 – HL3) as well as applications and requirements (R classes).

Demonstrator made of Luvocom 3F PEI 50236 GY (Source: Lehvoss Group)

With its product lines Luvosint and Luvocom 3F, the Lehvoss Group is offering a portfolio of tailor-made plastics for 3D printing. These products have been adapted to the most common production processes, such as powder bed fusion, fused filament fabrication (FFF) and fused granulate fabrication (FGF). The Luvocom 3F product series currently offers three products based on PEI, PPS, and PA that have been tested and classified for use in railway vehicles. The test specimens are manufactured in the FFF procedure. Tests are carried for smoke density (DIN ISO EN 5659-2) and oxygen index (DIN ISO EN 4589-2). The products Luvocom 3F PEI 50236 GYLuvocom 3F PPS CF 9938 BK and Luvocom 3F PAHT KK 50056 BK FR meet R22 and R23 in HL 1, HL 2 and HL3 and are thus suitable for a broad range of applications. PEI 50236 GY has a grey pigmentation to meet the industry demand, which obviates the need for a subsequent coating with colored paint.

All three products additionally comply with UL94 V0 above a wall thickness of 0.4 mm with 3D-printed test specimens.