High grade aluminium alloys usually refer to aluminum alloy materials that excel in key properties such as strength, hardness, corrosion resistance, thermal conductivity and electrical conductivity. They are widely used in high-end fields such as aerospace, automobile manufacturing, construction, and electronics.
High grade aluminum alloys classified by alloy system
- 2XXX series (Al-Cu-Mg)Aluminum Alloys
– Typical grades: 2024, 2A12, 2A14, etc.
– Features: high strength, good toughness and fatigue strength, excellent heat resistance and processing performance.
– Application scenarios: aerospace (aircraft structural parts, skins), defense industry (high-strength bolts), and civilian tools.
– Technological breakthroughs: Foreign countries have developed high damage tolerance alloys such as 2324 and 2624 for use on the lower wing surface, and China is accelerating to catch up.
- 5XXX series (Al-Mg)Aluminum Alloys
– Typical grades: 5052 (fatigue resistance, seawater corrosion resistance), 5083 (medium strength, good weldability), 5A06 (aircraft skin skeleton), 5086, 5059, 5754.
– Features: high specific strength, excellent weldability and corrosion resistance, and low density (about 2.7g/cm³).
– Application scenarios: ships (hull structure), automobiles (fuel tanks, gas cylinders), buildings (aluminum-plastic panels), marine engineering.
– Technical challenges: The high-end welding wire market is monopolized by ALCOA in the United States, and China needs to break through the sub-rapid solidification technology.
- 6XXX series (Al-Mg-Si)Aluminum Alloys
– Typical grades: 6061 (high strength, good corrosion resistance), 6063 (building profiles), 6082 (rail transportation).
– Features: medium strength, good corrosion resistance, processability and weldability, easy extrusion molding.
– Application scenarios: automobiles (body panels, luggage racks), buildings (doors and windows, curtain walls), industrial manufacturing (electronic accessories).
– Technical gap: The industrialization of domestic automobile body panels has just started, and it needs to benchmark European and American brands such as 6016 and 6022.
- 7XXX series (Al-Zn-Mg-Cu)Aluminum Alloys
– Typical grades: 7075 (super-hard aluminum, aviation grade), 7055 (for Boeing 777 aircraft, yield strength>620MPa).
– Features: Highest strength among aluminum alloys, excellent stress corrosion resistance.
– Application scenarios: aerospace (aircraft landing gear, load-bearing components), high-end equipment (high-stress molds).
– Technical bottleneck: China lacks system alloy design technology, and some products rely on imports.
- Aluminum-lithium alloy (Al-Li)
– Features: low density (10%~20% lighter than traditional aluminum), high elastic modulus, and good fatigue performance.
– Typical grades: US 2050/2198, domestic 1420 (for C919 passenger aircraft).
– Application scenarios: aviation (fuselage skin), aerospace (rocket, spacecraft).
– Technical gap: China can only produce limited grades, and high-end thick plates/large-diameter ingots need to be broken through.
Typical applications of high grade aluminium alloys in high-end fields
- Aerospace
– Fuse structure: 7050 and 2050 aluminum-lithium alloys are used in Boeing 787 wings, reducing weight by more than 15%;
– Engine parts: 2219 aluminum alloy is used in rocket fuel tanks, which are resistant to low temperatures (-253℃) and have stable strength.
- New energy vehicles and rail transit
– Battery housing: 6061-T6 aluminum alloy is formed by profile extrusion, which is impact-resistant and has good heat dissipation;
– High-speed train body: 5083 (Al-Mg) has excellent welding performance and is used to reduce the weight of high-speed rail carriages.
- Electronics and precision instruments
– Heat dissipation module: High-silicon aluminum alloy (Si content 40%-60%) has a thermal conductivity of 180-220 W/(m・K), which is used for 5G base station heat sinks;
– Optical frame: 7075-T6 is precision-processed, has high dimensional stability, and is used for telescope brackets.
High grade aluminum alloys cover 2XXX, 5XXX, 6XXX, 7XXX series and aluminum-lithium alloys. Through composition optimization (such as adding elements such as Cu, Mg, Zn, Li) and advanced processing technology (such as 3D printing and micro-alloying), they achieve properties such as lightweight, high strength and corrosion resistance, becoming a key material for modern industrial upgrading.