Preparation And Properties Of Fe-based Bulk Amorphous From Industrial Raw Materials

This research was implemented in accordance with the present situation of the application of high pure raw materials in the study of bulk amorphous alloy, aiming at reducing preparation cost and the realization of transition of bulk amorphous alloy from laboratory to large-scale application. The Fe-based bulk amorphous alloys were prepared with industrial pure raw materials. The glass formation ability (GFA) of industrial pure Fe-based bulk amorphous alloy was studied, and the effect of melting technics as well as the ratio of W to B on GFA. The structure and morphology of crystallines gained from crystallization of Fe₆₀Co₈Zr₁₀Mo₅W₂B₁₅ bulk amorphous alloy were identified with XRD and TEM. The thermal stability of Fe-based bulk amorphous alloy was studied with Kissinger equation and Delog-Ozawa equation. Its corrosive resistance in different acid, alkali and salt solutions was analyzed with full immersion method and X ray photoelectron technique. The mechanical properties as well as the friction and wear properties were investigated with indentation technique and other common experiments, and effect of heat treatment on these properties was also investigated. The magnetic characteristics of Fe-based bulk amorphous alloy were studied with vibrating sample magnetometer and magnetic balance.With industrial pure raw materials, Fe₆₀Co₈Zr₁₀Mo₅W₂B₁₅ bulk amorphous alloys were successfully prepared which have better GFA and thermal stability. The product after crystallization of Fe₆₀Co₈Zr₁₀Mo₅W₂B₁₅ bulk amorphous alloy is mainly composed of needle-like and granular α-Fe phase and bulk Fe₃B of tetragonal or orthorhombic structures. The casting mechanical properties of Fe₆₀Co₈Zr₁₀Mo₅W₂B₁₅ bulk amorphous alloys prepared both from industrial pure raw materials and high-pure raw materials are similar. Proper heat treatments of the cast alloys obtained with industrial pure raw materials increased the fracture toughness, hardness and wear resistance. High uniformity of the Fe-based amorphous alloy and quick formation of passive film composed of ZrO₂ are attributed to its good corrosive resistance. Some soft magnetic property was found in the cast Fe-based bulk amorphous alloy. Little effect of heat treatment on the magnetism was found before crystallization.