Crystallization of metallic glass Fe46Ni31VSi8B14

The crystallization behavior of a multi-component metallic glass Fe46Ni31VSi8B14 is examined in detail by using differential thermal analysis, X-ray diffraction, and electron microscope in-situ observation, etc. The crystallization of the glassy specimen proceeds in two steps, with (Ni, Fe) solid solution and α-Fe structure-like crystalline phase precipitating in the first stage, followed by three other crystalline phases, (FeNiV)3(SiB), Ni31Si12, and (FeNiV)23(SiB)6, forming in the metalloid-rich residual amorphous matrix in the second stage. It is noticed that the phase of α-Fe structure shows metastability and transformed gradually into (Ni, Fe) solid solution and (FeNiV)2(SiB). Almost immediately by the end of this process begins the transformation of other two metastable phases, i.e. (FeNiV)3(SiB) and (FeNiV)23(SiB)6, into stable phases, leaving finally in the specimen altogether three stable phases, (Ni, Fe) solid solution, Ni31Si12, and (FeNiV)2(SiB), in equilibrium. It follows from both the results and those for a few Fe- and Fe-Ni based multi-component metallic glasses that metastable and also stable crystalline phases would precipitate concurrently upon crystallization from the amorphous matrix of a multi-component metallic glass and the metastable phases transform sequentially into stable phases with further rise of temperature. (author)