Synthesis and thermal stability of B20-Type TMGe (TM = Mn, Fe and Co) intermetallic compounds prepared by mechanical milling

Abstract

We propose a new synthesis method of transition-metal monogermanides (TMGe, TM = Mn, Fe, and Co) with a B20-type chiral structure. Arc-melting followed by mechanical milling can be used to produce ∼70110Å-sized B20-type structures. Differential scanning calorimetry and heat-treatment tests indicated that the B20-phases are stable below 673 K, 873K and 773K for MnGe, FeGe and CoGe, respectively. We also demonstrated that sintering tests are able to yield dense compacts from the FeGe and CoGe B20-phase powders.