High-strength and high-toughness aluminum alloy material for bumper beam and method for manufacturing the same

Abstract

The present invention discloses a high strength and high toughness aluminum alloy for a bumper beam and a method for manufacturing the same. The method includes: casting into a billet an aluminum alloy which comprises aluminum as a principal element, silicon (Si) of 0.1 wt. % or less, ferrum (Fe) of 0.2 wt. % or less, copper of 0.45 wt. % to 0.60 wt. %, manganese (Mn) of 0.1 wt. % to 0.20 wt. %, magnesium (Mg) of 1.3 wt. % to 1.5 wt. %, chromium (Cr) of 0.1 wt. % or less, zinc of 4.5 wt. % to 5.1 wt. %, titanium (Ti) of 0.04 wt. % or less, zirconium (Zr) of 0.08 wt. % to 0.12 wt. %, and inevitable impurities of 0.15 wt. % or less; extruding the billet into a predetermined form to form an extrusion; performing a solid-solutionization process to quench the extrusion; subjecting the extrusion to an artificial age-hardening which is performed at a temperature of about 120° C. for 24 hours; and subjecting the extrusion an over age-hardening which is performed at a temperature of about 170° C. to 185° C. for 1 hour to 3 hours.

1 . An aluminum alloy material with high-strength and high-toughness, comprising:
 aluminum as a principal element, silicon (Si) of 0.1 wt. % or less, ferrum (Fe) of 0.2 wt. % or less, copper of 0.45 wt. % to 0.60 wt. %, manganese (Mn) of 0.1 wt. % to 0.20 wt. %, magnesium (Mg) of 1.3 wt. % to 1.5 wt. %, chromium (Cr) of 0.1 wt. % or less, zinc of 4.5 wt. % to 5.1 wt. %, titanium (Ti) of 0.04 wt. % or less, zirconium (Zr) of 0.08 wt. % to 0.12 wt. %, and inevitable impurities of 0.15 wt. % or less.   
   
   
       2 . A method for manufacturing an aluminum alloy material for a bumper beam, comprising:
 casting into a billet an aluminum alloy which comprises aluminum as a principal element, silicon (Si) of 0.1 wt. % or less, ferrum (Fe) of 0.2 wt. % or less, copper of 0.45 wt. % to 0.60 wt. %, manganese (Mn) of 0.1 wt. % to 0.20 wt. %, magnesium (Mg) of 1.3 wt. % to 1.5 wt. %, chromium (Cr) of 0.1 wt. % or less, zinc of 4.5 wt. % to 5.1 wt. %, titanium (Ti) of 0.04 wt. % or less, zirconium (Zr) of 0.08 wt. % to 0.12 wt. %, and inevitable impurities of 0.15 wt. % or less;   extruding the billet into a predetermined form to form an extrusion;   performing a solid-solutionization process to quench the extrusion;   subjecting the extrusion to an artificial age-hardening which is performed at a temperature of about 120° C. for 24 hours; and   subjecting the extrusion an over age-hardening which is performed at a temperature of about 170° C. to 185° C. for 1 hour to 3 hours.