A comparison on microstructure features, compression property and wear performance of TC4 and TC11 alloys fabricated by multi-wire arc additive manufacturing

Multi-wire arc additive manufacturing (MWAAM) enabled customized production with high deposition efficiency and low cost as compared to the common wire arc additive manufacturing (WAAM) technology. In this paper, two titanium alloy components were prepared using the MWAAM technique, and the microstructures, mechanical properties, and wear behaviors of Ti–6Al–4V (TC4) alloy and Ti-6.5A1-3.5Mo-1.5Zr-0.3Si (TC11) alloy were investigated. The results showed that the microstructure distribution of TC11 alloy prepared by MWAAM was more intensive and the length and width of the lamellar α-Ti phase were significantly reduced compared with that of TC4 alloy. The polar densities corresponding to the <110> texture in the two selected regions of the TC4 alloy and the TC11 alloy were 17.30 and 17.69, respectively. The proportion of the HAGBs of the TC4 sample and the TC11 sample were 99.07 % and 99.43 %, respectively. The average microhardness on the X–Y plane of TC4 and TC11 alloys were 316.17 HV and 366.14 HV, respectively, while the average microhardness on the Y-Z plane were 318.18 HV and 358.10 HV, respectively. The average compression yield strengths of TC4 and TC11 alloys were 836.61 MPa and 1088.33 MPa, respectively. The COFs of MWAAM TC4 and TC11 samples were stable at 0.479 and 0.455 under 20 N, respectively. The COFs of MWAAM TC4 and TC11 samples were stable at 0.472 and 0.432 under 60 N, respectively. The average yield strength, average ultimate strength, proportion of HAGBs, and microhardness of TC11 alloy were all higher than that of TC4 alloy. These results indicated that TC11 alloy had advantages over TC4 alloy in terms of mechanical properties and microstructure, with higher strength and deformation resistance. The properties of titanium alloy samples prepared by MWAAM were not lower than those of titanium alloy samples prepared by single wire WAAM, while MWAAM significantly better than single wire WAAM in deposition efficiency. The results obtained in this paper can help to prepare titanium alloy components with excellent mechanical properties more efficiently in MWAAM process.