Aluminum is one of the most commonly used metals in industrial production, especially in additive manufacturing. It is a high-strength, lightweight metal alloy with an ideal combination of mechanical and thermal properties. Companies engaged in material development, especially for additive manufacturing, provide various aluminum alloys for metal 3D printing.
In order to better understand the characteristics of this metal and its benefits for 3D printing components, TCT editor will take you to explore in depth in this article.
Aluminum (Al) has an atomic number of 13 and is a chemical element that can be found everywhere in the Earth's crust. It is a non-ferromagnetic metal that cannot be magnetized by a magnetic field. Many aluminum alloys that can be used for additive manufacturing are composed of a combination of metal and metalloid elements, including aluminum, silicon, magnesium, or copper. The most popular aluminum alloys include:
AlSi7Mg - Aluminum and magnesium alloys containing silicon (7%)
AlSi10Mg - Silicon containing aluminum alloy (10%) and magnesium alloy
AlSi12- Aluminum alloy containing silicon (12%)
AlSi9Cu3- Aluminum containing silicon alloy (9%) and copper (3%)
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Aluminum is not only a low melting point light metal, but also a very good electrical and thermal conductor. The industrial use of aluminum makes it one of the most important materials in terms of quantity and usage. So how is this metal applied in additive manufacturing?
There are many different methods for making 3D printed components using aluminum alloy. One of the most common techniques in metal additive manufacturing is laser powder bed fusion (LPBF), which uses laser to melt the metal layer laid on the powder bed point by point. The same applies to electron beam melting (EBM) technology, but the difference is that its energy source is an electron beam rather than a laser.
In addition to these two methods, there are other metal manufacturing methods that can also use aluminum for printing, such as adhesive spraying, cold metal melting (CMF), and wire arc additive manufacturing (WAAM). In addition, we also found that although FDM technology has relatively low applications for aluminum, it mainly uses plastic wire. However, some companies have developed solutions compatible with this technology to manufacture more wear-resistant parts.
Compared to other metals, aluminum 3D printing components have many advantages and disadvantages. Among them, aluminum is a high-performance material with interesting mechanical and chemical properties. In addition to being able to manufacture complex geometric structures, it also has high strength to weight ratio and weather resistance. However, aluminum 3D printed components are not as rigid as steel components. And unlike titanium, aluminum is not a biocompatible metal, so it is not an ideal choice for use in the medical field.
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Regardless of the process used, aluminum alloy 3D printed components can provide interesting features for many industries. In addition to having good chemical resistance and light weight, aluminum alloy is also one of the metals with the best strength to weight ratio among all metals. With the continuous and in-depth development of industry fields, the demand for material properties in various industries such as aerospace and automotive manufacturing is also rapidly increasing.
In the automotive industry, uses 3D printed aluminum pistons for its flagship model GT2 RS. The use of metal additive manufacturing technology enables the company to obtain up to 30 horsepower of power from a 700 horsepower twin turbocharged engine, while improving the efficiency and performance of the car. Meanwhile, Mercedes Benz is printing aluminum replacement parts for its truck and car production lines to ensure higher road safety.
In 2021, Ford announced plans to 3D print 200000 aluminum alloy parts annually. At that time, Ford was developing components that would be used for the full production of Ford's "very popular models". The details of the 3D printed parts to be mass-produced were not disclosed, but it can be confirmed that they will be manufactured using adhesive spray 3D printing technology.
The challenging metal powder used by Ford for binder injection and sintering is aluminum 6061. This development is the result of a collaboration between Ford engineers and materials scientists, as well as ExOne, a supplier of adhesive spraying technology. The significance of successfully applying aluminum to 3D printing production of automotive parts is significant: the transition from traditional manufacturing processes to 3D printing processes will simplify design to reduce weight, save space, improve part performance, and save costs and time.
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The aerospace industry is also unwilling to fall behind in its business by adopting aluminum 3D printing technology. For example, NASA's Marshall Space Flight Center conducted thermal tests on a 3D printed nozzle, which was developed in collaboration with a startup company, Elementum 3D, using a new aluminum alloy 6061-RAM2 developed by Elementum 3D and capable of withstanding huge temperature gradients. This type of nozzle is lighter than traditional nozzles, laying the foundation for deep space flight that can carry more payload.
According to TCT, the research team led by Wu Xinhua, the founder of Beifeng Technology (2024 TCT booth number: 7F50) and academician of the Australian Academy of Engineering, has successfully developed a high-temperature and high-strength 3D printing specific aluminum alloy material with the brand name GA570, which has immediately received high praise and attention from many aviation giants including General Motors, Boeing, Thor, Safran, and others. The strength of GA570 material has reached the highest level among aluminum alloy materials currently available for 3D printing, with a stable tensile strength of over 570MPa and an elongation rate of over 12%. The prepared aviation components have passed the stability test at a high temperature of 250 ºC for 5000 hours, which is equivalent to the requirement of 25 years of conventional engine service.
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Nowadays, many companies are committed to the development of aluminum powder. Including Zhongti New Materials (2024 TCT booth number: 8E62) and Anhui University of Engineering jointly developing low-cost and high-strength Al Ce aluminum alloy series materials, improving the strength and plasticity of alloys, and expanding their applications in aerospace, automotive and other fields, providing new theoretical basis and practical guidance for the innovative application of lightweight materials, and promoting technological innovation in the field of metal 3D printing.
And it is worth noting that 3D printing equipment manufacturer EOS (2024 TCT booth number: 8E30) officially launched the high-strength anodized aluminum alloy material Aluminum Al5X1 for industrial 3D printing this year, and began supplying it in November. Compared to other aluminum alloys with similar strength and elongation characteristics, this aluminum alloy has a more competitive cost. EOS Aluminum Al5X1 has excellent performance and material properties, combining high strength and elongation.
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EOS Aluminum Al5X1
With the continuous research and development of material technology, high-performance materials are constantly iterating in the development of aerospace technology. The emergence of new materials is constantly pushing traditional material technology forward. Aluminum materials face great challenges in performance and specifications, requiring aluminum alloy materials to be stronger, lighter, more reliable, and have longer lifespan. They should have service performance in extreme environments, high strength, toughness, corrosion resistance, fatigue resistance, and low residual stress after processing as large specification high-performance materials. TCT also believes that the development prospects of 3D printing of aluminum alloys are promising, especially in the fields of aerospace and industry.