Simple acid bath cuts surface roughness on 3D-printed titanium by 20%
Researchers found that soaking electron beam 3D-printed titanium parts in dilute hydrofluoric acid for two hours smooths their surfaces significantly, removing a major barrier to using additive manufacturing for aerospace and medical devices. The discovery could reduce post-processing costs and timelines for high-precision metal components.
Originaltitel: Effect of parametric modifications and post-processing on surface properties for Ti-6Al-4V manufactured using electron beam powder bed fusion
Electron beam powder bed fusion (PBF-EB/M) components typically exhibit high as-built surface roughness, partly due to powder sintering during the pre-heating stage. Post-processing techniques by chemical immersion in acids has been shown to reduce the surface roughness. A three-stage experimental approach was employed to investigate the post-processing chemical immersion technique for PBF-EB/M produced Ti-6Al-4 V ELI components. The experimental approach determined that using 1% hydrofluoric acid at room temperature with an immersion time of 120 min resulted in a reduction of various roughness parameters (Ra, Rq, Rz, Rp and Rv) by around 20% each. Additionally, two different EB scan strategies, continuous contouring and multi-spot contouring, were also investigated. The choice of scan strategy did not significantly affect the previously mentioned roughness parameters, however, continuous contouring did increase the Rsm significantly by 45%, and produced distinct changes in the surface morphology. The findings establish a reference for how chemical immersion and scan strategy selection affect surface characteristics, supporting future planned mechanical testing to evaluate their impact on the functional behaviour of PBF-EB/M Ti-6Al-4 V ELI components.