0000000000647978
AUTHOR
Antoine De Padoue Shyikira
showing 4 related works from this author
High temperature oxidation of higher manganese silicides
2021
Abstract The oxidation kinetics and mechanisms of higher manganese silicides (HMS) MnSi1.75, MnSi (1.75-x)Gex, MnSi(1.75-x)Alx (with x = 0.005 and 0.01)were studied and the effects of densification methods and dopant concentration discussed. Oxidation experiments were conducted using thermogravimetry (TGA), while post characterization with X-ray Photoelectron Spectroscopy (XPS) and Scanning Electron Microscope (SEM) showed that spark plasma sintering (SPS) is a better densification method than hot pressing (HP). Except for undoped HMS, HMS doped with 0.5at% Ge had the lowest oxidation rate. Stable formation of a SiO2 protective layer was the main reason for improved oxidation resistance in …
Long term stability of silicide based thermoelectric materials and modules
2023
Silicide-based thermoelectric generators are potential candidates for waste heat recovery at temperatures below 500 C. For the last two decades, the conversion efficiency of modules based on n-type magnesium silicides and p-type higher manganese silicide has improved significantly. However, the conditions in which thermoelectric generators operate (for example, remote areas in the oil, gas, and telecommunication industries, in automobiles, etc.) are harsh (corrosive, for example) and hostile (due to thermal instability). In this project, there was much focus on the stability of the thermoelectric modules, with special interest given to oxidation of the thermoelectric materials and module s…
Performance evaluation and stability of silicide-based thermoelectric modules
2020
Abstract Long-term studies on thermoelectric generators based on N-type magnesium silicide (Mg2.01Si0.49Sn0.5Sb0.01) and P-type higher manganese silicide (Mn0.98Mo0.02Si1.73Ge0.02) materials are presented, in the operating temperature range of 200 °C–400 °C. Emphasis is put on the performance and reliability of the current collector configuration, especially on the hot side of the module, and on the thermomechanical stresses that are created during operation and lifetime testing as a result of large temperature gradients experienced across the thermoelectric legs. With silver (Ag) paste as contact material, the long term-stability of the uni-couples was carried out on non-metalized legs and…
The effect of Mo and Ge reactive elements on high-temperature oxidation of higher manganese silicide
2021
Abstract Higher manganese silicide (HMS) alloys (Mnx-αMoαSiy-βGeβ (x = 0.99–1.011, α = 0.005–0.02, y = 1.75, β = 0.005–0.01)) were studied to elucidate the effect of Mo and Ge pertaining to oxidation. Oxidation experiments were conducted using thermogravimetry and characterized using x-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM). Isoconversion experiments below 450 °C, shows that doping (up to 2 at%) raises the oxidation potential of HMS. Isothermally, the oxidation rate reduces buy one order of magnitude by doping on Mn and/or Si sites from 0.5 to 2 at%, revealing that the dopants-based oxides do not lessen the robustness of SiO2 oxide.