Silicon has a corrosive effect on cemented carbide. Although aluminum alloys with more than 12% Si are generally called high-silicon aluminum alloys and diamond tools are recommended, this is not absolute. The increasing silicon content gradually increases the destructive power of the tool. Therefore, some manufacturers recommend the use of diamond tools when the silicon content exceeds 8%.
Aluminum alloys with a silicon content between 8% and 12% are a transitional range, and both ordinary cemented carbide and diamond tools can be used. However, when using cemented carbide, tools that have been PVD (physical coating) and do not contain aluminum elements and have a smaller film thickness should be used. Because the PVD method and the small film thickness make it possible for the tool to maintain a sharper cutting edge (otherwise, in order to avoid abnormal growth of the film at the cutting edge, the cutting edge needs to be sufficiently passivated, and cutting aluminum alloys will not be sharp enough), and the film material containing aluminum may cause the blade film layer to react with the workpiece material and destroy the combination of the film layer and the tool substrate. Because the superhard coating is mostly a compound of aluminum, nitrogen, and titanium, it may cause chipping due to a small amount of peeling of the cemented carbide substrate when the film peels off.
It is recommended to use one of the following three types of tools:
1. Uncoated ultra-fine-grained carbide tools
2. Carbide tools with non-aluminum coating (PVD) methods, such as TiN, TiC, etc.
3. Diamond tools
The chip space of the tool should be large. It is generally recommended to use 2 teeth, and the front angle and back angle should be large (such as 12°-14°, including the back angle of the end teeth).
If it is just general milling, you can use an indexable face milling cutter with a main deflection angle of 45°, equipped with a blade specially designed for processing aluminum alloys, which should have a better effect.
Alumina was converted into aluminum by electrolysis in the laboratory in 1808, and has been used as a building material on the spire of the Washington Monument in the United States since 1884; aluminum alloy materials synthesized by adding various metal elements to aluminum have been widely used in various links of the construction industry. Common thickness of aluminum alloy plates: advanced metal roof (and curtain wall) systems are generally 0.8-1.2mm (while traditional ones are generally ≥2.5mm).
