Preparation method for aluminum-boron intermediate alloy

The invention relates to a preparation method for an aluminum-boron intermediate alloy. The preparation method comprises the following steps that 1, molten aluminum with the temperature of 700-750 DEGC in an aluminum melting furnace is transferred into a power frequency furnace; 2, potassium fluotitanate accounting for 2% of the weight of the molten aluminum and potassium fluoborate accounting for 2% of the weight of the molten aluminum are uniformly mixed, then is added with the molten aluminum in the power frequency furnace, then, when the temperature of the molten aluminum reaches 800-830DEG C, the potassium fluoborate accounting for 33% of the weight and the potassium fluoborate accounting for 33% of the weight are added into molten aluminum in 2-3 batches, are stirred to be completely reacted to obtain an alloy molten aluminum; 3, the floating on the surface of the alloy molten aluminum is poured out or scooped off, then rice husks accounting for 1-3% of the weight of the moltenaluminum are scattered on