Welding aluminum alloy sheet for railway motor train set with two hundred kilometers per hour and manufacturing method

The invention discloses a weldable aluminum alloy plate for a railway motor train unit with the speed of 200km per hour and a manufacturing method and relates to an aluminum alloy plate and the manufacturing method thereof. The invention aims at solving the problems of heavy car body and high cost caused by the use of stainless steel plates in the railway motor train unit with the speed of 200km per hour currently. The plate comprises the following compositions by weight percent: 0.30% of Si, 0.35% of Fe, 0.20% of Cu, 0.20-0.70% of Mn, 1.00-2.00% of Mg, 0.30% of Cr, 4.00-5.00% of Zn, 0.20% of Ti, 0.25% of Zr, 0.10% of V and the balance of Al. The method comprises the following steps: setting the solid-melting treatment temperature between 468 and 472 DEG C; pre-stretching a thick plate for 60 to 90 minutes, and cold quenching in the water with the temperature below 34 DEG C. The plate has a tensile strength not smaller than 315N/mm , a disproportionate extension strength not smaller than 195N/mm , a simple process and a high qualified rate of products.