A Novel Nb-Based Eutectic Superalloy with Exceptional Ultrahigh-Temperature Mechanical Properties
Abstract
Refractory alloys operating above 1300 °C, beyond the limit of Ni-based superalloys, must balance high-temperature strength, thermal stability, low density, low cost, and room-temperature tensile ductility, a combination that existing refractory alloys have yet to achieve. Here we report a castable Nb-based eutectic superalloy, Nb-10Mo-9.5C (at. %, NMC-1), comprising a uniform lamellar structure of Nb-Mo solid solution and Nb2C carbide phases. NMC-1 achieves 0.2% yield strengths of ~300 MPa and ~200 MPa at 1300 °C and 1500 °C, respectively, among the highest reported for Nb-based alloys, with pronounced strain hardening, non-zero room-temperature tensile ductility, and no observed microstructural coarsening after 100 h at 1400 °C. Its low density (8.65 g/cc) and cost (~$85/kg) yield a specific-strength-per-cost merit index that far surpasses commercial Nb, Mo, Ta, and W alloys, establishing a new design paradigm for ultrahigh-temperature structural materials.
Related
- Achieving ultrahigh-temperature superfluidity in atomic Fermi gases by suppressing pairing fluctuations
- First-Principles-Informed Modeling of Thermal Transport and Laser-Induced Heating in Ultrahigh-Temperature Carbides
- High-temperature mechanical spectroscopy of yttria-stabilized tetragonal zirconia polycrystals (Y-TZP) with different amounts of intergranular phase
- Additive manufacturing of a Ni-20 wt%Cr binary alloy by laser powder bed fusion: Impact of the microstructure on the mechanical properties
- Investigation of the influence of the temperature on the fracture properties of adhesive joints using the Arcan device
BibTeX
@misc{nahin2026novel,
title = {{A Novel Nb-Based Eutectic Superalloy with Exceptional Ultrahigh-Temperature Mechanical Properties}},
author = {Ayeman M. Nahin and Alfredo Navarrete and Xiaokun Yang and Eric A. Lass and Mingwei Zhang},
howpublished = {arXiv},
year = {2026},
month = sep,
doi = {10.48550/arxiv.2609.06848},
eprint = {2609.06848},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2609.06848},
note = {CC BY-NC-ND 4.0},
}
RIS
TY - UNPB
TI - A Novel Nb-Based Eutectic Superalloy with Exceptional Ultrahigh-Temperature Mechanical Properties
AU - Ayeman M. Nahin
AU - Alfredo Navarrete
AU - Xiaokun Yang
AU - Eric A. Lass
AU - Mingwei Zhang
PY - 2026
DA - 2026/09/06
PB - arXiv
DO - 10.48550/arxiv.2609.06848
UR - https://arxiv.org/abs/2609.06848
AB - Refractory alloys operating above 1300 °C, beyond the limit of Ni-based superalloys, must balance high-temperature strength, thermal stability, low density, low cost, and room-temperature tensile ductility, a combination that existing refractory alloys have yet to achieve. Here we report a castable Nb-based eutectic superalloy, Nb-10Mo-9.5C (at. %, NMC-1), comprising a uniform lamellar structure of Nb-Mo solid solution and Nb2C carbide phases. NMC-1 achieves 0.2% yield strengths of ~300 MPa and ~200 MPa at 1300 °C and 1500 °C, respectively, among the highest reported for Nb-based alloys, with pronounced strain hardening, non-zero room-temperature tensile ductility, and no observed microstructural coarsening after 100 h at 1400 °C. Its low density (8.65 g/cc) and cost (~$85/kg) yield a specific-strength-per-cost merit index that far surpasses commercial Nb, Mo, Ta, and W alloys, establishing a new design paradigm for ultrahigh-temperature structural materials.
ER -