Laser engraving on aluminum

The versatility of aluminum

Aluminum is the third most abundant chemical element in the Earth’s crust, making up approximately 8% of its mass. It is identified with the symbol Al and atomic number 13 in the periodic table. It is a flexible, light, malleable, resistant metal, with high thermal and electrical conductivity.

Its resistance to corrosion and its ability to be recycled without losing its properties make it a very valuable material in many industries, including automotive, aerospace, and construction.

Aluminum as engravable material

Aluminum can be engraved both in depth and for marking.

Deep engraving involves removing material to create a design or text on the surface of the aluminum. This process can be performed with cutting tools or lasers, and is commonly used to create nameplates, signs, and industrial components.

Marking is a surface process that does not remove material, but rather changes the color of the aluminum surface to create a design or text. This process is commonly performed with a laser and is used to create barcodes, serial numbers, and logos on aluminum products.

Aluminum as a weldable material

Despite the difficulties, aluminum is a weldable material with both laser and TIG (Tungsten Inert Gas).

Laser welding is a fast and precise process that uses a concentrated beam of light to melt and join aluminum parts. It is especially useful when high precision and speed are required, such as in electronic component manufacturing or the aerospace industry.

TIG welding is a process that uses a non-consumable tungsten electrode to produce the weld and inert gas to protect the weld area from atmospheric contamination. This method is ideal for jobs that require high welding quality, such as in the manufacture of aluminum structures for construction or the automotive industry.

Both processes require skill and experience, as aluminum has high thermal conductivity and can be difficult to weld without warping the part. However, with the right technique, aluminum can be welded to create strong and durable structures.

How is aluminum obtained?

Aluminum is primarily extracted from bauxite, a type of sedimentary rock that has a high aluminum content. This is crushed and mixed with caustic soda and water, forming a pulp. It is heated under high pressure to dissolve the aluminum oxide from the bauxite and obtain alumina, which is separated from other impurities present in the pulp using sulfuric acid.

Alumina is smelted in furnaces at temperatures above 2000°C, using coal as fuel. Liquid aluminum is obtained by electrolysis of molten alumina. Alumina (Al2O3) dissolved with cryolite in an electrolytic cell (Na3AlF6) that has its interior covered with carbon. This liquid aluminum is poured into molds and allowed to cool and solidify. It is then cut and molded to obtain the desired shape.

Heat treatments can be applied to aluminum to improve its properties and a surface finish is given (polished, anodized, painted, etc.)

The main aluminum deposits are located in Australia, Brazil, Africa and the Caribbean, and the main producing countries are China and Russia. In addition, much of the aluminum produced worldwide comes from recycling.