Overview
Aluminum alloy 2007, a short-chipped aluminum alloy, has a copper content of 3.3-4.6% resulting in its low weldability and low corrosion resistance. It is especially used for producing turned parts owing to its excellent machinability and heat treatability, such as washers, bolts, nuts, and other kits in the automotive industry, and more.
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What is Aluminum 2007?
Aluminum alloy 2007 is a high-strength aluminum alloy with main composition of aluminum, copper and some other elements. It represents the 2000 series of aluminum alloys with excellent mechanical properties and machinability. Alloying of aluminum 2007 with copper improves its strength properties without harming its machinability. This alloy is one of the most common base materials used in those applications requiring high strength and excellent machinability, such as in the production of precision components, fasteners, and fittings in the aerospace, automotive, and industrial machinery industries. Moreover, aluminum 2007 has excellent corrosion resistance, allowing it use in different environments.
What Are the Common Characteristics of Aluminum Alloys in the 2000 Series?
The 2000-series aluminum alloys possess several beneficial features, such as high strength and good machinability, that have ensured their use in fields where structural integrity and stiffness are vital. The combination of remarkable strength-to-weight ratios, however, these materials lack corrosion resistance to a degree that other aluminum series will provide. Therefore, they are cold-rolled so that during heat treatment, hardening through heat treatment processes could be done. In spite of their high copper content, which can be a cause for concern in terms of weldability, they have wide applications in aerospace, automotive and structural engineering. With their usage ranging from aircraft components to automotive wheels, where high strength and stiffness are critical requirements, their importance cannot be over-emphasized.
Chemical Composition of Aluminum 2007
| Chemical Element | % Present |
|---|---|
| Manganese (Mn) | 0.50 – 1.00 |
| Iron (Fe) | 0.0 – 0.80 |
| Magnesium (Mg) | 0.40 – 1.80 |
| Silicon (Si) | 0.0 – 0.80 |
| Copper (Cu) | 3.30 – 4.60 |
| Zinc (Zn) | 0.0 – 0.80 |
| Titanium (Ti) | 0.0 – 0.20 |
| Nickel (Ni) | 0.0 – 0.20 |
| Lead (Pb) | 0.80 – 1.50 |
| Bismuth (Bi) | 0.0 – 0.20 |
| Tin (Sn) | 0.0 – 0.20 |
| Chromium (Cr) | 0.0 – 0.10 |
| Other (Each) | 0.0 – 0.10 |
| Others (Total) | 0.0 – 0.30 |
| Aluminium (Al) | 87.5 – 95.0 |
The Influence of Composition on the Properties of Aluminum 2007
The performance characteristics (corrosion resistance, the strength-to-weight ratio, formability, etc.) primarily depend on the composition of the aluminum alloy 2007 which is the combination of aluminum and copper-based on the reinforcements of trace elements like magnesium, manganese, and silicon. Copper is the most important alloying component of the alloy, and evidently, the enhancement of strength of the alloy under the presence of heat is significant. Beyond other additions, impurities, and trace elements can modify properties like machinability, corrosion resistance, and mechanical strength. Apart from this heat treatment additionally improves mechanical characteristics via precipitation of the strengthening phases in the microstructure. Generally, exactness of modulation of composition and processing properties is highly critical to specify the characteristics of 2007 aluminum so that it perfectly meets specific application and hinders the degradation of desired properties in use situations.
Mechanical Properties of Aluminum 2007
| Properties | Metric | Imperial |
| Tensile strength | 370-420 MPa | 54000-61000 psi |
| Yield strength | 240-270 MPa | 34000-40000 psi |
| Shear strength | 220-250 MPa | 32000-36000 psi |
| Fatigue strength | 91-110 MPa | 13000-16000 psi |
| Elastic modulus | 71 GPa | 10300 ksi |
| Poisson’s ratio | 0.33 | 0.33 |
| Elongation | 5.6-8.0% | 5.6-8.0% |
| Hardness, Brinell | 130 | 130 |
Physical Properties of Aluminum 7007
| Density | Solidification range | Electr. Conductivity | Thermal conductivity | Modulus of elasticity | Specific heat | Shear modulus |
| 2.85 g / cm³ | 507-650 °C | 18-22 MS / m | 130-160 W / (mK) | 72,500 MPa | 860 J / (kg-K) | 27,300 MPa |
Heat Treatment of Aluminum 7007
| Soft annealing, recrystallization annealing | |
| Annealing temperature | 380 – 420 °C 1-2 h |
| Heat-up time | 1 – 2 h |
| Cooling conditions | > 250 °C: ≤ 30°C / h ≤ |
| Hardening | |
| Solution annealing | 480 – 490 °C |
| Quenching | Water up to 65 °C |
| Natural aging | 5 – 8 days |
Challenges Encountered in Processing Aluminum 2007
Due to the high copper content of this aluminum alloy 2007, it can be difficult to process it. Machining complications such as tool wear and poor surface finish happen from a presence of copper which means the cutting parameters and the methods of chip control need to be handled with special care. Heat treatment must be carefully regulated to obtain its specified strength properties without excessive deformation. Although welding creates trouble, it is of paramount importance to use some unique procedures so as to crack the weld. The meet of these concerns is achieved through application of quality measures such as process planning, tool selection, and parameter optimization which result in the production of good quality aluminum 2007.
Equivalent Materials of Aluminum 2007
| US | AISI(UNS) | A92007 |
| ISO | Designation | AlCu4PbMgMn |
| European Union | Numerical (Chemical symbols) | EN AW-2007 (EN AW-AlCu4PbMgMn) |
The Price of Aluminum 2007
As of January 2022 the price of aluminum alloy 2007 was about $2,200- $2,500 t/metric ton. Nevertheless, the price changes may occur in the long-run as a consequence of factors such as market demand, supply chain dynamics, geopolitical events, and fluctuations of the raw material costs. It is very important to bear in mind that the most precise and accurate pricing information can be found in the current market data, which in its turn can be taken from the reputable sources or directly from the aluminum suppliers.
Common Application Fields of Aluminum 2007
Multipurpose alloy 2007 is highly appreciated due to its wide range of applications. It is rather commonly used in the manufacture of aerospace fasteners and structural parts, automotive engines, and marine boat fittings. Its high machinability makes it suitable to precision part manufacturing in the agriculture and electrical, among others. Besides, it is applied in sports equipment such as parts of a bicycle. Aluminum 2007 is strong, machine-able, easy to use, and shows good resistance to corrosion. Consequently, it is used in many different areas.
