Effect of support structure on part build using selective laser melting / Muhammad Rafi Sulaiman

• Main Author: Muhammad Rafi , Sulaiman
• Format: Thesis
• Published: 2024
• Subjects: TJ Mechanical engineering and machinery
• Online Access: http://studentsrepo.um.edu.my/15417/2/Muhammad_Rafi.pdf; http://studentsrepo.um.edu.my/15417/1/Muhammad_Rafi_Sulaiman.pdf; http://studentsrepo.um.edu.my/15417/

Selective Laser Melting is a metal Additive Manufacturing process used to synthesize three-dimensional object in which successive layers of material are formed under computer control to create the object. To successfully produce metal parts by SLM, additional support structures are needed to support overhanging surfaces in order to dissipate process heat, minimize geometrical distortions induced by internal stresses and hold the work piece in its place. In this work, an experimental investigation was carried out to optimize the parameter of contour support structure which is contour offset, teeth height, teeth top length and teeth base length. The design of experiments was conducted using Taguchi’s L16 orthogonal array. The effect of support structure parameter toward the residual stress of part, volume of support, build time and support removal time were investigated. Furthermore, a statistical tool analysis by utilizing signal-to-noise response and analysis of variance (ANOVA) was used to obtain the optimal and significant support structure parameter. The result indicates amount of residual stress, time required for support removal and build time are significantly influenced by contour offset, while all parameters are significant for support volume. The optimum parameter to get low residual stress is contour offset is 0.6 mm, teeth height is 1.4 mm, teeth top length is 0.75 mm and teeth base length is 1.55 mm. Samples with lower deflection exhibit smaller average melt pool areas compared to those with higher deflection, with the regions closer to the support showing an average depth of 148 micrometers compared to 205 micrometers in regions farther from the support. The distortion results obtained from simulating with Simufact Additive exhibit a strong agreement when compared to the deformations observed in experimental data.