Fusing agent for non-vacuum casting zinc alloy, and preparation method

The invention relates to a fusing agent for non-vacuum casting zinc alloy, and a preparation method. The fusing agent comprises the following components in percentage by weight: 5-50% of magnesium carbonate, 25-47.5% of sodium chloride, and 25-47.5% of potassium chloride. The preparation method of the fusing agent comprises the following steps: separately sieving a certain amount of the magnesium carbonate, a certain amount of the sodium chloride and a certain amount of the potassium chloride with a sieve of 20-320 meshes; drying the sieved magnesium carbonate, the sieved sodium chloride and the sieved potassium chloride in an air drying oven under 170 DEG C for 15min so as to remove crystal water; uniformly mixing and stirring the dried magnesium carbonate, the dried sodium chloride and the dried potassium chloride so as to obtain a mixture; packaging the mixture, and storing the packaged mixture under dry environment. The fusing agent disclosed by the invention covers the liquid surface of a cast fusant, so that the liquid surface is closely sealed, and the liquid surface cannot be in contact with air and be oxidized; the harmful gases in the zinc alloy fusant can be effectively exhausted; the oxides in the zinc alloy fusant can be remained on the surface of the fusing agent; besides, the fusing agent has the effects of refinement, slag removal, gas removal and purification on the fusant.