The invention belongs to the technical field of preparation of aluminum
alloy sections, and relates to a wide-range thin-wall series-6 aluminum
alloy section for a
high speed train and a preparation method of the wide-range thin-wall series-6 aluminum
alloy section. Aluminum alloy comprises the following elements in percentages by weight: 0.50-0.65% of Si, less than or equal to 0.25% of Fe, less than or equal to 0.10% of Cu, 0.03-0.15% of Mn, 0.45-0.55% of Mg, less than or equal to 0.05% of Cr, less than or equal to 0.05% of Zn, less than or equal to 0.10% of Ti, less than or equal to 0.05% ofa single
impurity, less than or equal to 0.15% of total impurities and the balance of Al. Deformation resistance and friction resistance in an extruding process are reduced by reasonably controllingthe temperature relationship of an
ingot casting, an
extrusion barrel and a die, the extruding speed is increased to be 8-13 m / min, the
quenching temperature of the product is ensured, thus, any coarse grain rings are not generated when a thin-walled apron board is extruded at high speed, after being subjected to on-line
quenching, the product is directly subjected to artificial
ageing at the temperature of 175+ / - 5 DEG C for 4-8 hours, the
mechanical property of the product can meet requirements in TB / T.3260.4-2011 TO 1.2 mm thin-walled sections, the actual tensile strength reaches 250-270 MPa, the yield strength reaches 210-230 MPa, the specific elongation is 8-10%, and the grade of the grain size of an aluminum section microscopic structure reaches and even exceeds 4.