Fabrication and thermoelectric properties of β-FeSi2 prepared by mechanical alloying

摘要

Thermoelectric β-FeSi2 was successfully fabricated by mechanical alloying followed by sintering process.The influence of milling time and sintering conditions on alloying progress was studied by X-ray diffraction.The electrical and thermoelectric properties of undoped β-FeSi2 and Mn-doped β-FeSi2 were both measured for comparison.The results show that the powder,which is mechanically alloyed by milling for 50 h,is completely changed into β-FeSi2 phase after sintering at 890 °C for 15 h in Ar atmosphere.The maximum value of power factor of Fe0.92Mn0.08Si2is 28.5 μW·m-1·K-2 at 600 °C,while that of FeSi2 is only 6.6μW·m-1·K-2.