Towards production of landing gear materials with laser powder bed fusion

Abstract

Titanium 10 V-2Fe-3Al (Ti 10-2-3) coupons were produced via laser powder bed fusion and characterized. Results indicate that coupons produced by the additive manufacturing process have substantially lower high-cycle fatigue strength compared to wrought material (40 vs. 90 ksi, or 276 vs. 621 MPa at runout, respectively). Low-cycle fatigue strength of the printed coupons was also lower than wrought coupons (1000 cycles to failure at 0.75% strain for printed coupons vs 1% strain for wrought), but there was significant overlap in the data between printed and wrought. Failure analysis and optical microscopy revealed that the printed coupons showed microstructural differences when compared to wrought, such as larger grains and smaller dimples in the fracture surfaces. Computed tomography revealed defects in printed coupons. After a 500 h salt-spray, no corrosion was visible in printed Ti 10-2-3 material. At this time, Ti 10-2-3 landing gear components which are not safety critical and do not experience cyclic loading over 10,000 cycles may be considered for production via laser powder bed fusion.