| Microstructure of Steel Samples Manufactured by Wire-Arc Additive Manufacturing in the Presence of Inter-Pass Cold Working |
| Paper ID : 1211-UFGNSM-FULL |
| Authors: |
|
Behzad Parvaresh *1, Reza Miresmaeili2 1Department of Materials Engineering,Tarbiat Modares University,Jalal Ale Ahmad Highway, P.O.Box: 14115-143, Tehran, Iran 2Department of Materials Engineering, Tarbiat Modares University, P.O. Box: 14115-143, Tehran, Iran |
| Abstract: |
| The wire and arc-based additive manufacturing technology (WAAM) locally adds material to the molten pool. Parts produced by this technology can have significant residual stress, distortion and large grain sizes. To overcome these challenges, each welded layer was inter-pass cold worked. Cold working induced grain refinement when the cold worked material was reheated during the next deposition pass. By this procedure, recrystallization may be occurred and after that we would have new stress-free grains that result in eliminating distortion and decreasing residual stresses. In this study, the effect of inter-pass cold working on the microstructure and mechanical properties of samples prepared by WAAM technology was studied. To evaluate these, two samples were prepared by WAAM technology which used CMT-P as arc welding source and 347 SS wire as a metal feed. First sample prepared without any cold working but other sample cold worked between each layer. To characterize the microstructure, Optical Microscopy was used. To prove occurrence of recrystallization, Vickers Micro hardness was used. As a result, Vickers micro hardness of the layers first enhanced because of cold working but after reheating generated from subsequent welding layers, Vickers micro hardness of the cold worked layers decreased. OM results showed the differences between microstructures of samples with or without cold working. By this results, it was concluded that sample with inter-pass cold working had been recrystallized. |
| Keywords: |
| Additive Manufacturing, WAAM, Stainless Steel 347, Mechanical Properties, Microstructure. |
| Status : Paper Accepted (Oral Presentation) |
