Aluminum is the most common material among non-ferrous metals. It has a variety of characteristics not found in ferrous metal materials, and is therefore widely used. In product design, we need to fully understand these characteristics to select the appropriate material type, processing method, heat treatment, etc.cnc aluminum parts This time, we will explain the properties and types of aluminum.

Characteristics of aluminum

1. Light and strong

Steel has a specific gravity of about 7.9, while aluminum has a specific gravity of about 2.7, and weighs only about one-third as much as steel. On the other hand, the strength is about 70% of that of general structural steel.aluminum t profile Therefore, aluminum is a material with high specific strength (strength per unit weight).

2. Not easy to rust

Aluminum has the property that the surface is always covered with a very thin film of oxide. It acts as a protective film, and it is difficult for corrosion problems to go deeper than the oxide film.led panel aluminum frame Therefore, we don't need antirust coating and plating.

3. Easy processing

Aluminum has good ductility and is suitable for plastic processing. It has low melting point and good fluidity, so it is also suitable for forging. It is easy to cut and weld.

4. Good thermal and electrical conductivity

Aluminum is a material with high thermal conductivity. Therefore, it is used as a radiator for air conditioning or engine cooling water. In addition, it has good electrical conductivity and is lightweight, so it is also used as a transmission line material.

Considerations for Aluminum

1. Low strength

Although aluminum has a high "specific strength," it has a low strength compared to steel. Although it is suitable for flexible structures like airplane wings, it is not suitable for gears that require strength.

2. Corrosion can occur under certain conditions.

Although aluminum is not susceptible to rust, it sometimes corrodes when exposed to salty environments or dissimilar metals. Therefore, to avoid corrosion, it is necessary to treat aluminum oxide film.

3. Large coefficient of linear expansion

The coefficient of thermal expansion of aluminum is almost twice that of iron. As a result, large thermal stresses are generated, and thermal fatigue and damage may occur when aluminum is used as a part that is repeatedly heated and cooled.

4. No fatigue limit

In the case of ferrous materials, there is generally a "lower stress limit" or "fatigue limit" where metal fatigue does not occur. In other words, if the design only produces a variable load that is lower than the "fatigue limit," it is theoretically possible to use the material permanently. However, since aluminum does not have such a "fatigue limit," it is necessary to compare the variable stress generated during use and the SN line graph, etc., during design to confirm that there will not be a strength problem even if cracking intensifies during the envisioned service life of the product.