Novel specimen geometries for fatigue testing of additive manufactured metals under axial, torsion, and combined axial-torsion loadings

摘要: Abstract Using the geometric freedom offered by additive manufacturing, a plate-type specimen geometry for axial fatigue testing, hollow cylindrical torsion and two thin-walled circular cross section specimens or axial-torsion testing are proposed. The proposed geometries reduce stress concentration at gage-to-grip transition area, improve uniformity of shear distribution throughout wall thickness, increase buckling resistance during compression part loading cycle. Some preliminary test results conducted with presented compared conventional ASTM tubular specimen.