Lightweight smelting flux capable of being reutilized as well as preparation method and application of lightweight smelting flux

The invention relates to the technical field of welding, in particular to a light smelting flux capable of being reutilized and a preparation method and application of the light smelting flux. The light smelting flux capable of being reutilized is prepared from the following components in percentage by mass: 37%-41% of SiO2, 26%-30% of MnO, 11%-13% of MgO, 13%-16% of Al2O3, 3%-5% of CaF2 and 2%-3% of Fe2O3. The light smelting flux can be reutilized, and the mechanical property of a weld joint formed after secondary welding is excellent. The invention further provides a preparation method of the light smelting flux capable of being reused. The method has the advantages of being easy to operate, short in technological process, suitable for batch production and the like. The invention further provides application of the light smelting flux capable of being reutilized in welding, resource and energy waste can be avoided, and production and machining cost can be reduced. 本发明涉及焊接技术领域，具体而言，涉及一种可二次利用的轻质熔炼焊剂及其制备方法和应用。