Aluminum extrusion molding process characteristics

Posted on :June 13th，2024 By GREFEE

Aluminum extrusion molding is a plastic processing method that applies strong pressure to the metal billet in the mold cavity (or extrusion cylinder), forcing the metal billet to undergo directional plastic deformation and being extruded from the holes of the mold to obtain the required cross-sectional shape, size, and mechanical properties of parts or semi-finished products.

Classifications of aluminum extrusion molding

According to metal plastic formation flowing directions, extrusion can be classified into below types:

Forward extrusion: During production, the direction of metal flow is the same as the direction of punch movement

Reverse extrusion: During production, the direction of metal flow is opposite to the direction of punch movement

Composite extrusion: During production, a portion of the metal flow direction of the billet is the same as the movement direction of the punch, while another portion of the metal flow direction is opposite to the movement direction of the punch.

Radial extrusion: During production, the direction of metal flow is 90 degrees away from the direction of punch movement.

Characteristics of aluminum extrusion molding：

1. During the extrusion process, the extruded metal can obtain a stronger and more uniform three-dimensional compressive stress state in the deformation zone than in rolling and forging, which can fully utilize the plasticity of the processed metal itself.

2. Extrusion molding can not only produce rods, tubes, profiles, and wire products with simple cross-sectional shapes, but also produce profiles and pipes with complex cross-sectional shapes.

3. Extrusion molding has great flexibility, only requiring the replacement of molds and other extrusion tools to produce products with different shapes, specifications, and varieties on one device. The operation of replacing extrusion molds is simple, fast, time-saving, and efficient.

4. The precision of extruded products is high, the surface quality of the products is good, and the utilization rate and yield of metal materials are also improved.

5. The extrusion process has a good impact on the mechanical properties of metals.

6. The technical process is efficient and is convenient to produce. One time of extrusion can obtain larger overall structural components than hot forging or forming rolling methods, with less equipment investment, low mold cost, and high profit.

7. Aluminum alloys have good extrusion properties and are particularly suitable for extrusion processing. They can be processed through various extrusion processes and mold structures.

Advantages of aluminum extrusion molding:

1. Improve the deformation ability of aluminum. Aluminum is in a strong triaxial compressive stress state in the extrusion deformation zone, which can fully achieve its plasticity to obtain large deformation.

2. The comprehensive quality of the product is high. Extrusion molding improves the structure of aluminum and enhances the mechanical properties. After quenching and aging, the longitudinal (extrusion direction) mechanical properties of the extruded products are much higher than those of similar products produced by other processing methods. Compared with processing methods such as rolling and forging, extruded products have higher dimensional accuracy and better surface quality.

3. Wide product range. Extrusion molding not only produces pipes, rods, and wires with simple cross-sectional shapes, but also produce solid and hollow profiles with very complex cross-sectional shapes, and variable cross-sectional profiles with gradually varying cross-sectional shapes along the length direction. Many products with cross-sectional shapes cannot be formed using other plastic processing methods. The size range of extruded products is also very wide, from ultra large pipes and profiles with a cross-sectional outer circle diameter of 500-1000mm to ultra small precision profiles with a cross-sectional size similar to that of a matchstick.

4. High production flexibility. Extrusion molding has great flexibility. The products with different shapes, sizes, and varieties on the same equipment can be made easily via the method of changing molds. The operation of changing the mold is simple, convenient, time-consuming, and efficient.

5. Simple process flow and low equipment investment. Compared to pipe and profile production processes such as perforation rolling and pass rolling, extrusion forming has advantages such as short process flow, fewer equipment and investment.

Disadvantages of aluminum mold extrusion：

1.Uneven organizational performance of the product. Due to the uneven flow of metal during extrusion (especially severe in non-lubricated forward extrusion), the microstructure and properties of the extruded products are uneven between the surface and center, as well as between the head and tail.

2. The working conditions of extrusion molds are harsh, and the wear and tear of the molds are high. During extrusion, the billet is in an approximately closed state with high three-dimensional pressure, so the mold needs to withstand high pressure. At the same time, during hot extrusion, the mold is usually subjected to high temperature and high friction, which greatly affects the strength and service life of the mold.

3. Low production efficiency. In addition to the continuous extrusion method, conventional extrusion methods cannot achieve continuous production. In general, the extrusion speed is much lower than the rolling speed, and the geometric waste loss and yield of extrusion production are large.

In recent years, due to a large demand of miniaturization and lightweighting in all kinds of industries, aluminum and aluminum alloy have been widely applied into construction, transportation, electronic device and aerospace, the need of aluminum extrusion products has increased significantly.

MORE BOLG

Insert mold in injection mold service

What are advantages and disadvantages of Zinc alloy and Aluminum alloy?

Inspection standards for injection molded partappearance

How to judge the quality of your plastic products?

Inspection standards for CNC machining

To ensure that your products are 100% qualified

Categories