Research Projects

Global energy efficiency and environmental imperatives drive a shift in high-temperature material design. Conventional Ni-based superalloys, though widely used, suffer from high density (8-9 g/cm³), high cost, and rely on critical elements. While refractory additions (W,Mo,Re,Ru) enhances high-temperature performance[1], it significantly increases density, cost and also induces casting defects[2] that reduce processability. These challenges highlight the urgent need to develop alternative high-temperature alloys that are lightweight, cost-effective, and environmentally sustainable. Recent alloy development has focused on systems that mimic the γ′-strengthening mechanism of superalloys, exhibiting an impressive strength-ductility synergy[3].Chen et al.[4] reported that a Ni-Co-Cr-Al-Ti-based alloy achieved high-temperature yield strength of approximately 578 MPa at 1000℃, matching 2nd gen. superalloy DD5 (574.8 MPa). However, prolonged high-temperature exposure causes γ′ precipitate coarsening and instability, which degrade its volume fraction, size, and thermal stability, leading to reduced creep resistance and overall mechanical properties. Previous γ′ stabilization efforts in high temperature alloy systems faced instability [5,6] or the concurrent formation of undesirable brittle phases [7,8].Nevertheless, Fe-Co-Ni-Cr-Al-Ti based alloys have recently shown promise. For example, Yeh et al. [9] reported stable γ′ precipitates in Fe11.5Co20.6Ni40.7Cr12.2Al7.8Ti7.2 (at%) alloys with solvus temperatures up to 1146-1194 ℃ and densities as low as 7.64-7.94 g/cm³. Similarly, Chao Liu et al. [10] developed a Fe31.4Ni33.2Co13.4Cr13.8Al3.1Ti2.2Nb1.1Mo1.7C0.03B0.015Zr0.03 (wt%) alloy with coherent γ′ nanoparticles within an FCC matrix and a density of 7.71 g/cm³, which is ≈6.14% lower than that of Ni-based superalloys (8.2-9 g/cm3). The specific strength at 1023 K (96.4 MPa/g·cm-3) surpassed IN718Plus (75.4)[11] and IN740H (77.9) [10] Despite attempts to reduce density and cost by using Al, Ti, and Fe [12,13], determining optimal compositions for achieving phase stability, reduced density, and low cost simultaneously remains an underexplored challenge. This proposal aims to design and optimize next-generation lightweight Fe-Co-Ni-Cr-Al-Ti-based alloys for high-temperature applications (e.g., turbine blades and combustion chambers) aiming for significantly lower costs without compromising properties. Overcoming traditional design's limitations, Machine Learning (ANN, SVM, RF, KNN) and CALPHAD will predict optimal compositions and properties (strength, creep, density, oxidation resistance). Subsequently, Experimental validation will involve alloy synthesis via arc/VIM and high-temperature creep and oxidation testing (700-1100℃). Aligned with circular economy principles, this work promotes the use of recyclable, abundant elements and energy-efficient processes to develop cost-effective, sustainable materials for next-generation aerospace and energy systems