TY - JOUR

T1 - Microstructure, mechanical and tribological properties of a Ti-5Cu alloy and a B4C/Ti-5Cu in situ composite fabricated by laser powder bed fusion

AU - Ren, Y.

AU - Wu, H.

AU - Agbedor, S.-O.

AU - Lu, Y.

AU - Zhang, Y.

AU - Fang, Q.

AU - Li, J.

AU - Tian, Y.

AU - Baker, I.

PY - 2022/10/31

Y1 - 2022/10/31

N2 - Both a novel Ti-5Cu alloy (in wt%) and a Ti-5Cu in situ composite containing 1 wt% B 4C were fabricated by laser powder bed fusion, and their microstructures, mechanical and tribological properties were systematically investigated. The microstructure of the Ti-5Cu was mainly composed of α Ti laths, Ti 2Cu and retained β phases, while the B 4C/Ti-5Cu composite was composed of α Ti laths, Ti 2Cu, TiC, TiB and TiB 2 phases. Both the Cu and B 4C additions promoted a transition from columnar to equiaxed grains for prior-β and α phases. The B 4C/Ti-5Cu composite was found to have a higher hardness (467 HV) than the Ti-5Cu (417 HV). Further, the composite exhibits a yield strength of 1100 MPa and an ultimate tensile strength of 1250 MPa. Values which are higher than those of the Ti-5Cu that exhibits a yield strength of 750 MPa and an ultimate tensile strength of 900 MPa. However, this strength increase comes at the expense of a reduction in elongation to failure from 6.2% to 1.5%. Even though the composite is significantly stronger, the two materials exhibited very similar wear rates (ω B4C/Ti-5Cu = 4.95 × 10 −4 mm 3 N −1 m −1 and ω Ti-5Cu = 4.85 × 10 −4 mm 3 N −1 m −1).

AB - Both a novel Ti-5Cu alloy (in wt%) and a Ti-5Cu in situ composite containing 1 wt% B 4C were fabricated by laser powder bed fusion, and their microstructures, mechanical and tribological properties were systematically investigated. The microstructure of the Ti-5Cu was mainly composed of α Ti laths, Ti 2Cu and retained β phases, while the B 4C/Ti-5Cu composite was composed of α Ti laths, Ti 2Cu, TiC, TiB and TiB 2 phases. Both the Cu and B 4C additions promoted a transition from columnar to equiaxed grains for prior-β and α phases. The B 4C/Ti-5Cu composite was found to have a higher hardness (467 HV) than the Ti-5Cu (417 HV). Further, the composite exhibits a yield strength of 1100 MPa and an ultimate tensile strength of 1250 MPa. Values which are higher than those of the Ti-5Cu that exhibits a yield strength of 750 MPa and an ultimate tensile strength of 900 MPa. However, this strength increase comes at the expense of a reduction in elongation to failure from 6.2% to 1.5%. Even though the composite is significantly stronger, the two materials exhibited very similar wear rates (ω B4C/Ti-5Cu = 4.95 × 10 −4 mm 3 N −1 m −1 and ω Ti-5Cu = 4.85 × 10 −4 mm 3 N −1 m −1).

KW - Composite

KW - Laser powder bed fusion

KW - Mechanical properties

KW - Titanium‑copper alloy

KW - Wear rate

U2 - 10.1016/j.matchar.2022.112217

DO - 10.1016/j.matchar.2022.112217

M3 - Journal article

VL - 192

JO - Materials Characterization

JF - Materials Characterization

SN - 1044-5803

M1 - 112217

ER -