2-series aluminum alloy profile with low fatigue crack growth rate and manufacturing method thereof

• Main Authors: SUN YOUZHENG, CAO SHANPENG, MA JUNXING, TANG HEZHUANG, WANG XINGRUI, ZHOU KUANG, YANG XIN
• Format: Patent
• Language: Chinese; English
• Published: 21.03.2023
• Subjects: ALLOYS; AUXILIARY OPERATIONS USED IN CONNECTION WITH METAL-WORKINGWITHOUT ESSENTIALLY REMOVING MATERIAL; CASTING; CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES; CHANGING THE PHYSICAL STRUCTURE OF NON-FERROUS METALS ANDNON-FERROUS ALLOYS; CHEMISTRY; FERROUS OR NON-FERROUS ALLOYS; MANUFACTURE OF METAL SHEETS, WIRE, RODS, TUBES OR PROFILES,OTHERWISE THAN BY ROLLING; MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVINGMATERIAL; METALLURGY; PERFORMING OPERATIONS; POWDER METALLURGY; PRETREATMENT OF RAW MATERIALS; PRODUCTION AND REFINING OF METALS; PUNCHING METAL; TRANSPORTING; TREATMENT OF ALLOYS OR NON-FERROUS METALS

A 2-series aluminum alloy profile with a low fatigue crack propagation rate comprises, by mass, less than 0.05% of Si, less than 0.06% of Fe, 3.7%-4.1% of Cu, 1.2%-1.4% of Mg, 0.6%-0.8% of Mn, less than 0.02% of Cr, 0.02%-0.06% of Ti, less than 0.05% of other impurity elements and the balance Al, the contents of Cu and Mg need to be adjusted synchronously, the ratio of Cu to Mg is kept to be 2.9-3.1, and the balance is Al. A gradient heating isothermal backward extrusion technology is adopted, the deformation temperature of the profile is accurately controlled, dynamic recrystallization is inhibited, dynamic recovery is promoted, the extrusion effect of the profile is enhanced through the large extrusion ratio of 25-40, and the damage tolerance and fatigue performance of the profile in the L-T direction are remarkably improved. 一种低疲劳裂纹扩展速率2系铝合金型材，所述合金型材中各物质的质量百分比为：Si含量低于0.05％，Fe含量低于0.06％，Cu含量3.7％～4.1％，Mg含量1.2％～1.4％，Mn含量0.6％～0.8％，Cr含量低于0.02％，Ti含量0.02％～0.06％，其他杂质元素含量低于0.05％，余量为Al，其中Cu、Mg含量调整需同步，保持Cu/Mg比为2.9～3.1