Vehicle baggage rack sectional material and preparing method thereof

The invention relates to a vehicle baggage rack sectional material and a preparing method thereof. According to the following sectional material preparing steps, an aluminum alloy cast bar containingsilicon, magnesium, copper, manganese, chromium, molybdenum, nickel, tungsten and cobalt is selected, the aluminum alloy cast bar is heated and subjected to heat preservation, then, the heated aluminum alloy cast bar is quenched after being cooled, and the quenched aluminum alloy cast bar is subjected to tempering treatment; an extrusion die is heated and subjected to heat preservation, an extrusion material barrel is heated, then, the aluminum alloy cast bar is placed in an extrusion barrel, the aluminum alloy cast bar in the extrusion barrel is pushed to be extruded out of the position of adie opening of the extrusion die, and an extrusion sectional material is formed; the extrusion sectional material at the die opening position of the extrusion die is subjected to air-cooling cooling,and the temperature of the