7068 aluminium alloy is one of the strongest commercially available aluminium alloys, with a tensile strength comparable to that of some steels. This material, also known as an aircraft alloy, is heat treatable. [1]
7068-T6511 has typical ultimate tensile strength of 710 MPa (103 ksi) versus a similar product produced from 7075-T6511 that would have a typical ultimate tensile strength of 640 MPa (93 ksi). Typical yield strength for alloy 7068-T6511 is 683 MPa (99.1 ksi) versus 590 MPa (86 ksi) for a similar product produced from 7075-T6511. [2] Strength allowables for this alloy are provided in Metallic Materials Properties Development and Standardization for design. [3]
The main alloying elements are zinc (7.3 to 8.3%), magnesium (2.2 to 3.0%), copper (1.6 to 2.4%) and zirconium (0.05 to 0.15%), with traces of silicon, iron, manganese, chromium, and titanium. [4]
| Element [4] | Weight percentage (%) |
|---|---|
| Aluminum, Al | 85.43 |
| Zinc, Zn | 8.3 |
| Magnesium, Mg | 3 |
| Copper, Cu | 2.4 |
| Iron, Fe | 0.15 |
| Zirconium, Zr | 0.15 |
| Silicon, Si | 0.12 |
| Manganese, Mn | 0.1 |
| Titanium, Ti | 0.1 |
| Chromium, Cr | 0.05 |
| Other (each) | 0.05 |
| Other (total) | 0.15 |
| Properties [4] | Metric |
|---|---|
| Density | 2.85 g/cm3 |
| Melting point | 476–635 °C |
| Properties [4] | Metric |
|---|---|
| Tensile strength | 641 MPa |
| Yield strength | 590 MPa |
| Elongation | 8% |
| Properties [4] | Metric |
|---|---|
| Thermal conductivity | 190 W/mK |
7068 alloy is a 7000 series aluminium-zinc alloy registered with the US Aluminium Association and produced to AMS 4331 (chemical composition and mechanical properties) and AMS 2772 (heat treatment). 7068 alloy ‘A’ and ‘B’ tensile data and fatigue properties have been ratified for inclusion in MIL Handbook 5 / MMPDS.
Primarily developed for ordnance applications, alloy 7068 is now being used or considered for markets like the aerospace and automotive industries (valve body and connecting rod applications), medical devices, such as prosthetic limbs, as well as recreational products like bicycles and mountain-climbing equipment. [5]
Applications of this alloy include: Connecting rods, Shock absorbers, Fuel pumps, Rocker arms, Bearing caps, Prosthetics, Chain tensioners. [6]
Standard specifications for AL 7068 include: [7]
6061 aluminium alloy is a precipitation-hardened aluminium alloy, containing magnesium and silicon as its major alloying elements. Originally called "Alloy 61S", it was developed in 1935. It has good mechanical properties, exhibits good weldability, and is very commonly extruded. It is one of the most common alloys of aluminium for general-purpose use.
7075 aluminium alloy (AA7075) is an aluminium alloy with zinc as the primary alloying element. It has excellent mechanical properties and exhibits good ductility, high strength, toughness, and good resistance to fatigue. It is more susceptible to embrittlement than many other aluminium alloys because of microsegregation, but has significantly better corrosion resistance than the alloys from the 2000 series. It is one of the most commonly used aluminium alloys for highly stressed structural applications and has been extensively used in aircraft structural parts.
2024 aluminium alloy is an aluminium alloy, with copper as the primary alloying element. It is used in applications requiring high strength to weight ratio, as well as good fatigue resistance. It is weldable only through friction welding, and has average machinability. Due to poor corrosion resistance, it is often clad with aluminium or Al-1Zn for protection, although this may reduce the fatigue strength. In older systems of terminology, 2XXX series alloys were known as duralumin, and this alloy was named 24ST.
5086 aluminium alloy is an aluminium–magnesium alloy, primarily alloyed with magnesium. It is not strengthened by heat treatment, instead becoming stronger due to strain hardening, or cold mechanical working of the material.
AA 6063 is an aluminium alloy, with magnesium and silicon as the alloying elements. The standard controlling its composition is maintained by The Aluminum Association. It has generally good mechanical properties and is heat treatable and weldable. It is similar to the British aluminium alloy HE9.
5083 aluminium alloy is an aluminium–magnesium alloy with magnesium and traces of manganese and chromium. It is highly resistant to attack by seawater and industrial chemicals.
7005 is an aluminium wrought alloy used in bicycle frames. Due to its relative ease of welding, it does not require expensive heat treating. It is, however, harder to form, making manufacture more challenging. It has an Ultimate Tensile Strength of 350 MPa, a Fatigue Strength of 150 MPa and a density of 2.78 g/cm3. It does not need to be precipitation hardened, but can be cooled in air.
5059 aluminium alloy is an aluminium–magnesium alloy, primarily alloyed with magnesium. It is not strengthened by heat treatment, instead becoming stronger due to strain hardening, or cold mechanical working of the material.
2014 aluminium alloy (aluminum) is an aluminium-based alloy often used in the aerospace industry.
5154 aluminium alloy is an alloy in the wrought aluminium-magnesium family. As an aluminium-magnesium alloy, it combines moderate-to-high strength with excellent weldability. 5154 aluminium is commonly used in welded structures such as pressure vessels and ships. As a wrought alloy, it can be formed by rolling, extrusion, and forging, but not casting. It can be cold worked to produce tempers with a higher strength but a lower ductility. It is generally not clad.
5454 aluminium–magnesium alloy is an alloy in the wrought aluminium-magnesium family. It is closely related to 5154 aluminium alloy. As an aluminium-magnesium alloy, it combines moderate-to-high strength with excellent weldability. Like 5154, 5454 aluminium is commonly used in welded structures such as pressure vessels and ships. As a wrought alloy, it can be formed by rolling, extrusion, and forging, but not casting. It can be cold worked to produce tempers with a higher strength but a lower ductility. It is generally not clad.
5456 aluminium–magnesium alloy is an alloy in the wrought aluminium-magnesium family. While it is closely related to 5356 aluminium alloy, it is used in structural applications, like most other aluminium-magnesium alloys, and not as filler for welding. As a wrought alloy, it can be formed by rolling, extrusion, and forging, but not casting. It can be cold worked to produce tempers with a higher strength but a lower ductility. It is susceptible to exfoliation corrosion when held at temperatures above 65 °C (150 °F) for extended periods of time.
5754 aluminium–magnesium alloy is an alloy in the wrought aluminium -magnesium family. It is closely related to the alloys 5154 and 5454. Of the three 5x54 alloys, 5754 is the least alloyed, but only by a small amount. It is used in similar applications. As a wrought alloy, it can be formed by rolling, extrusion, and forging, but not casting. It can be cold worked to produce tempers with a higher strength but a lower ductility.
6005 aluminium alloy is an alloy in the wrought aluminium-magnesium-silicon family. It is closely related, but not identical, to 6005A aluminium alloy. The main difference between the two alloys is that 6005 has a higher minimum composition percentage of aluminium than 6005A. The most common forming method is extrusion. It can also be forged or rolled, but as a wrought alloy it is not used in casting. It is commonly heat treated to produce tempers with a higher strength at the expense of ductility.
6005A aluminium alloy is an alloy in the wrought aluminium-magnesium-silicon family. It is closely related, but not identical, to 6005 aluminium alloy. Between those two alloys, 6005A is more heavily alloyed, but the difference does not make a marked impact on material properties. It can be formed by extrusion, forging or rolling, but as a wrought alloy it is not used in casting. It cannot be work hardened, but is commonly heat treated to produce tempers with a higher strength at the expense of ductility.
6060 aluminium alloy is an alloy in the wrought aluminium-magnesium-silicon family. It is much more closely related to the alloy 6063 than to 6061. The main difference between 6060 and 6063 is that 6063 has a slightly higher magnesium content. It can be formed by extrusion, forging or rolling, but as a wrought alloy it is not used in casting. It cannot be work hardened, but is commonly heat treated to produce tempers with a higher strength but lower ductility.
6105 aluminium alloy is an alloy in the wrought aluminium-magnesium-silicon family. It is one of the least common of the alloys in this series. While most wrought aluminium alloys are covered by multiple standards, 6105 is only dealt with in ASTM B221: Standard Specification for Aluminum and Aluminum-Alloy Extruded Bars, Rods, Wire, Profiles, and Tubes. It is formed by extrusion, and supplied in heat treated form. It can alternately referred to by the UNS designation A96105.
6162 aluminium alloy is an alloy in the wrought aluminium-magnesium-silicon family. It is related to 6262 aluminium alloy in that Aluminum Association designations that only differ in the second digit are variations on the same alloy. It is similar to 6105 aluminium alloy, both in alloy composition and the fact that it is only really used in extrusions. However, as a wrought alloy, it can also be formed by rolling, forging, and similar processes, should the need arise. It is supplied in heat treated form. It can be referred to by the UNS designation A96162, and is covered by the standard ASTM B221: Standard Specification for Aluminum and Aluminum-Alloy Extruded Bars, Rods, Wire, Profiles, and Tubes.
6262 aluminium alloy is an alloy in the wrought aluminium-magnesium-silicon family. It is related to 6162 aluminium alloy, but sees much more widespread use. It is notably distinct from 6162, and most other aluminium alloys, in that it contains lead in its alloy composition. It is typically formed by extrusion, forging, or rolling, but as a wrought alloy it is not used in casting. It can also be clad, but that is not common practice with this alloy. It cannot be work hardened, but is commonly heat treated to produce tempers with a higher strength but lower ductility.
The 6463 aluminium alloy is an aluminium alloy in the wrought aluminium-magnesium-silicon family. It is related to 6063 aluminium alloy, but unlike 6063 it is generally not formed using any processes other than extrusion. It is commonly heat treated to produce tempers with a higher strength but lower ductility. Like 6063, it is often used in architectural applications.