Abstract
Purpose - This paper aims to investigate approaches to optimize shape accuracy, dimensional accuracy and density of customized orthodontic production fabricated by selective laser melting (SLM).Design/methodology/approach - A series of process experiments were done to fabricating customized brackets directly by SLM, using 316L stainless steel. Shape accuracy was optimized through the study on fabricating characteristics of non-support overhanging structure. A scanning strategy combining contour scanning with orthogonal scanning, which differ in scanning speed and spot compensations, was proposed to improve dimensional accuracy. And scanning laser surface re-melting was added to enhance the SLM density.Findings - Optimized SLM process parameters lead to high shape accuracy of customized brackets, and the average dimensional error of bracket slot is less than 10µm. The customized brackets density is more than 99%, and the surface quality and mechanical properties could meet the requirements of orthodontic production.Research limitations/implications - Originality/value - This study presents the state-of-the-art in SLM of customized orthodontic production (especially medical appliance) with optimized part properties. It’s the first time that SLM is employed in the manufacturing of customized orthodontic products. This paper also shows original research on building overhang structures and a compound scanning strategy that could optimize SLM part accuracy. An improved Laser Surface Re-melting process is employed in the density optimization.
Purpose - This paper aims to investigate approaches to optimize shape accuracy, dimensional accuracy and density of customized orthodontic production fabricated by selective laser melting (SLM).Design/methodology/approach - A series of process experiments were done to fabricating customized brackets directly by SLM, using 316L stainless steel. Shape accuracy was optimized through the study on fabricating characteristics of non-support overhanging structure. A scanning strategy combining contour scanning with orthogonal scanning, which differ in scanning speed and spot compensations, was proposed to improve dimensional accuracy. And scanning laser surface re-melting was added to enhance the SLM density.Findings - Optimized SLM process parameters lead to high shape accuracy of customized brackets, and the average dimensional error of bracket slot is less than 10µm. The customized brackets density is more than 99%, and the surface quality and mechanical properties could meet the requirements of orthodontic production.Research limitations/implications - Originality/value - This study presents the state-of-the-art in SLM of customized orthodontic production (especially medical appliance) with optimized part properties. It’s the first time that SLM is employed in the manufacturing of customized orthodontic products. This paper also shows original research on building overhang structures and a compound scanning strategy that could optimize SLM part accuracy. An improved Laser Surface Re-melting process is employed in the density optimization.