Effect of edge distance-diameter ratio on pin-bearing strength of TC18 by laser melting deposition

Abstract This paper presents an experimental study on the pin-bearing characteristics of TC18 titanium alloy produced by laser melting deposition. Two types of specimens with edge distance-to-diameter ratios (e/D) were manufactured for pin-bearing tests. The S-Basis values of bearing strength are calculated based on statistical analysis of experimental data. The results indicate that the S-Basis value of bearing ultimate stress with e/D =1.5 specimens is 1648.12 MPa, and the S-Basis value of bearing ultimate stress is 1967.89 MPa for e/D =2.0 specimens. The S-Basis value of bearing ultimate stress for e/D=2.0 specimens is higher by 19.4% than that of e/D=1.5. The test result showed three different failure modes: shear-out, cleavage, and bearing. Each failure mode depends on the specific hole edge geometry adopted. The proportion of shear-out failure for e/D=1.5 samples is more than for e/D=2.0 specimens.