The role that aluminium powder plays in the powder metallurgy sector and other industrial segments should not be underestimated. However, what are the advantages of using this particular metal powder and which problems might arise during processing? We will be revealing all the details in the following article.
Whether it is used as aluminium foil, takes the shape of a fold-up garden chair or a particularly lightweight component in the automotive industry: Aluminium is omnipresent in everyday life as well as the industrial environment, whereby not only solid material is resorted to. It is primarily aluminium powder which is used in numerous areas of application and industries:
- Additive manufacturing
- Paints and varnishes
- Chemical catalysts
- The production of medicines
- Cosmetics production
- Explosives and fireworks
- Production of alloys for the mechanical engineering and vehicle construction sectors
Advantages of aluminium powder
Not without reason is aluminium powder used in a broad range of applications. The fine particles offer specific advantages – scoring points across all the different industries.
Advantage No. 1: Improved material properties
Due to the comparatively high costs, pure aluminium is seldom used. Instead, this substance is used to enhance other materials. If aluminium powder is used as an additive during casting or compacting, for example, this can lead to an improvement in specific material properties. Primarily, this concerns:
- Impact resistance
- Pressure resistance
- Thermal conductivity
- Corrosion resistance
- UV resistance
- Suitability for food applications
- Low weight
Particularly in the case of high-stress components that are partially exposed to adverse conditions, aluminium can improve performance. Through using it as an alloy, the positive properties can thus be easily passed on to the desired components.
Advantage No. 2: Recycling aluminium to create a powder offers inexpensive, sustainable alternatives
Despite aluminium’s being the third most common element in the earth’s crust, it does not occur in its pure form so that it needs to be extracted in an energy and time-consuming process, which in turn results in high costs. This pure light metal is not only accordingly expensive but also does not enjoy a particularly good reputation in terms of environmental protection.
On the other hand, recycling aluminium – in particular, when this involves the production of so-called secondary powders – is easier on resources and significantly cheaper. Therefore, recycled aluminium powders, gained from residual waste material, might provide an attractive alternative to working with solid aluminium or other light metal powders when it comes to profitability and sustainability. Today, the recycling rate for aluminium has almost reached the 70% mark within Europe. Compared to the primary production process, recycling can lead to 95% energy savings.
Disadvantages of aluminium powder
Alongside the energy consumption and cost aspects, one of the primary things to think about when using aluminium powder are the risks involved in its processing. Even at room temperature, ultra-fine aluminium quickly reacts with oxygen, thus making it necessary to install appropriate safety measures at your company and ensure that your personnel are professionally trained. In this connection, different sources of danger are important:
- Aluminium powder is combustible and flammable.
- If aluminium powder mixes with the air, this can result in a dust explosion.
- Highly flammable hydrogen may be produced, if the powder comes into contact with water, acids or alkalis.
- Reactions also take place with oxidants, such as nitrates and sulphates – with the risk of fire and explosion.
- Electrostatic charge build-up may result in electrical discharges that could cause an aluminium dust cloud to ignite.
To minimise these risks and prevent accidents and injury, it is absolutely essential to ensure that the material is stored properly, and that rooms and personnel are accordingly equipped. Much of this, however, also applies to handling other metal powders, such as titanium, so that switching to or adding aluminium powder does not actually entail that many changes. The measures and regulations to be observed include the following:
- Use conductive, earthed packaging materials
- Store in dry conditions
- Keep cool
- Store separately from incompatible substances and fluids.
Room and equipment requirements
- High level of cleanliness to avoid the accumulation of dust
- Avoidance of potential sources of ignition (open flames, hot surfaces etc.)
- Ventilation through natural or technical means
- Possibility of inertisation in order to interrupt the supply of oxygen in an emergency
- Respiratory equipment
- Hand protection
- Head and face protection: Helmet with a heat and flame-resistant mesh
- Work garments made of special flame-retardant fabric, with conductive properties
- Foot protection in the shape of conductive safety shoes
For all the components of a protective equipment kit, attention should be paid to observing the respective DIN standards in order to ensure maximum protection.
The star amongst the light metal powders
Due to its numerous exciting properties, aluminium powder continues to enjoy high popularity – regardless of the sector or industry involved. And if you include the possibilities in the field of additive manufacturing, even more ideas and innovations can be implemented using this special powder. Companies that have already gained experience in handling metal powders and have established appropriate safety standards should not shy away from using aluminium powder and exploit the potential offered by this material to their advantage.