FOCUS ON WELDING
CMT welding process
3D printing works with various processes . Wire-based processes such as “ Fronius Additive ” melt the welding wire , building up the workpiece layer by layer . To stop too much heat flowing into the workpiece , they must be designed to apply as little energy as possible .
The MIG-based Cold Metal Transfer welding process ( CMT ) from Fronius is especially suitable for metal 3D printing of aluminium components . CMT is a “ cool ” dip transfer arc process that minimises the heat input , despite its high deposition rate . This process is therefore suitable for additive welding , where the cyclical build-up of beads causes a high heat input .
CMT supports functions that are suited to metal 3D printing . “ Power correction ” is a typical example . This function allows the electrical power to be precisely adjusted to the respective process phase while the deposition rate remains constant .
“ With our CMT Additive Pro functions , specifically developed for additive manufacturing , such as power correction ( or the Deposition Stabiliser that keeps the deposition rate constant ), we can precisely control the power input and therefore the height and width of the weld ,” explained Leonhard Reiter from Fronius R & D .
Simulation of layer build-up and welding sequence .
Leonhard Reiter from Fronius R & D .
Standards for metal 3D printing are now available in North America , and are in progress for additively manufactured , unfired pressure vessels in Europe
Supporting new standards
Martin Lohr , IWE and Dr . Kati Schatz of Linde Engineering .
Fronius also supports the development of standards for additively manufactured components and pressure equipment . As a member of the “ Joint working group for additively manufactured components under the Pressure Equipment Directive of the German Institute for Standardisation ( DIN ),” Fronius participated in the model qualification of an additively manufactured component in collaboration with MIGAL . CO , Linde Engineering and TÜV SÜD . The working group assessed the applicability of the draft standard prEN 13445-14 to the components of unfired pressure vessels .
Drawing on their areas of expertise , the participating partners carried out material qualification ; design review ; process qualification ; additive manufacturing ;
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