Work

Creep properties of refractory niobium alloy at low temperature: Powder metallurgy vs wire-arc additive manufacturing

Year: 2025

Type: article

Abstract: This study examines the low-temperature, high-stress creep behavior of a niobium-based alloy, Nb–1 wt.% Zr, produced by wire-arc additive manufacturing (WAAM), in comparison with its powder metallurgy (PM) counterpart. Creep tests conducted at 300 °C showed that deformation in both materials was largely governed by the primary creep stage. WAAM specimens failed at 150 MPa, whereas PM specimens endured up to 250 MPa, demonstrating its superior creep strength. WAAM specimens exhibited greater strain accumulation (~3.5% at 150 MPa) and stronger stress sensitivity. Fractographic analysis revealed that WAAM specimens fractured primarily along interdendritic regions, while PM alloy failed due to void formation at grain boundaries and triple points. To capture strain evolution during primary creep, empirical fits based on logarithmic and power-law functions were applied, with the logarithmic model providing the best fit. These findings demonstrate that WAAM-induced microstructural features degrade creep resistance relative to PM processing and offer an empirical framework for describing primary creep strain evolution in Nb–Zr alloys under low-temperature, high-stress conditions.

Source: International Journal of Refractory Metals and Hard Materials

DOI: 10.1016/j.ijrmhm.2025.107568

Authors: Gazi Tanvir, Saiful Islam, Md Abdul Karim, Brian Bates, Yongho Jeon, Duck Bong Kim

Institutions: University of Georgia, University of South Carolina Aiken, Tennessee Technological University, Ajou University

Language: English

Topic: High Temperature Alloys and Creep

Subfield: Mechanical Engineering

Field: Engineering

Domain: Physical Sciences

Open Access status: hybrid

Estimated APC paid: $3,310

Funders: National Science Foundation, National Research Foundation of Korea, Ministry of Science and ICT, South Korea