Experimental Study of Implementation of Octagonal Internal Structure for Investment casting SL Patterns

摘要

This paper presents the experimental study of octagonal lattice structure for investment casting stereolithography patterns, and comparing it with the former hexagonal structure of the QuickCast 2.0 buildstyle. This research aims to introduce a new internal structure for investment casting SL patterns. In this study, a simple 3D coupled thermal-mechanical finite element analysis; magnitudes of exerted hoop stresses on ceramic shell (during burnout stage) have been calculated. Therefore a new generation of internal structure (or a new buildstyle) for investment casting SL patterns is presented here. The significant reduction of critical loadings on ceramic shell will ensure investment casting process via using SL patterns of an octagonal internal structure. As an experimental observation of stress evaluation for hexagonal and octagonal models, magnitudes of hoop and axial strains have been evaluated by installing self-temperature compensation strain gauges, for cylindrical models. Numerical results for new octagonal structure indicate that, there is a 62% reduction in maximum hoop stresses exerted on the ceramic shell. Moreover, a significant reduction of strain has been observed in both hoop and axial strains applying strain-gauging analysis (near 50% reduction).