A METHOD FOR CONTROLLING THE CASTING DEFECT OF AL-SI-MG ALLOY THROUGH GRAIN REFINEMENT AND IMPROVING THE COOLING SPEED BY USING HYDROPULSE

摘要

PURPOSE: A method for controlling welding defects by reducing aluminum-silicon-magnesium alloy particle size and improving cooling rate is provided to minimize the size of a needle-shaped insertion phase and reduce the amount of the needle-shaped insertion phase in welding. CONSTITUTION: A method for controlling welding defects reduces the particle size of Al-Si-Mg alloy and improves cooling rate by electromagnetic pulse treatment which removes welding defect of Al-Si-Mg alloy by irradiating the Al-Si-Mg alloy with the electromagnetic pulse form an electromagnetic pulse generators. The electromagnetic pulse generator which comprises a wave guide for transferring the electromagnetic pulse to the inside of a weld can reduce the size of the Al-Si-Mg alloy particle and improves cooling rate. The material of the wave guide is titanium material. The wave guide is located in the inside of the weld. The Al-Si-Mg alloy is an Al-6-7 wt% of Si-Mg alloy which is a 356 or 357 alloy. [Reference numerals] (AA) Untreated with electromagnetic pulses; (BB) Treated with electromagnetic pulses of 2Hz; (CC) Treated with electromagnetic pulses of 4Hz; (DD) Treated with electromagnetic pulses of 6Hz