McNair Scholars Research Journal
Abstract
Additive manufacturing, or 3D printing technologies, has been extensively used to develop evidence-based methods to construct lower-limb prosthetic sockets. However, the resulting structural, or 3D-printed materials behavior, is not well understood. With the intent of supporting evidence-based design guidelines to print amputee-specific sockets, the structural behavior of successfully-worn transtibial check sockets made from PCTG and printed from the FDM 3D printing process was benchmarked. Specifically, ASTM D638 type I tensile test specimens were die-cut from sheets of material with the 3D-printed characteristics of the check socket. Test samples were cut parallel and perpendicular to the print direction and tested according to ASTM D638. From the measured load-elongation data, stress-strain curves and the corresponding material properties were derived, including modulus of elasticity E, Poisson’s ratio ν, yield strength Sy, and ultimate strength Su. Based on t-test results, the modulus of elasticity E and ultimate strength Su were directionally dependent. However, variations associated with Poisson’s ratio ν and yield strength Sy were insignificant.
Keywords: 3D printing, lower-limb prosthetic socket, additive manufacturing, tensile properties