The main feature of aluminum profile brittleness is that it collapses during cutting and is easy to break during cold punching, which is reflected in both physical and mechanical properties. The brittleness will play a certain role in terms of the appearance of the section and the degree of recognition of the aluminum alloy door and window manufacturers, and affect the market share and user reputation of these aluminum profile manufacturers.

There are many reasons for the physical and mechanical properties of aluminum products, mainly as follows:

1. The mold design of aluminum profiles is unreasonable

1. The design of the die section is unreasonable, especially the distribution of the inner reinforcement and the treatment of the interface angle. This creates stress concentrations that require improved design and elimination of right and sharp angles at the interface.

2. The pressure of the die head is insufficient. The pressure at the die head is directly determined by the compression ratio of the die, especially the length of the straight section of the die. If the compression ratio of the die head is too small or the straight section is too short, the product will not be dense and the physical properties will be affected. On the one hand, the die head pressure can be changed to adjust the flow resistance by changing the length of the straight section of the die head; The compression ratio of the extruder screw is adapted; the melt pressure can also be changed by changing the formula, adjusting the extrusion process parameters, and adding a perforated plate.

3. For the performance decline caused by the poor convergence of the shunt ribs, the length of the rib and the outer surface, the length of the rib and the rib confluence should be appropriately increased, or the compression ratio should be increased.

4. The discharge of the die is uneven, resulting in inconsistent wall thickness of the profile or inconsistent density. This also results in the difference in mechanical properties between the two sides of the profile. In our experiments, one side is qualified and the other is unqualified, which just proves this. As for non-standard profiles such as thin walls, I won't say more here.

5. The cooling rate of the stereotyped mold. The cooling water temperature often does not attract enough attention. The function of the cooling water is to cool and shape the stretched macromolecular chain in time to achieve the purpose of use.

2. Unreasonable formula and mixing process

1. Too much filler.

2. The type and quantity of impact modifiers are unreasonable.

3. Too much or too little stabilizer.

4. Excessive amount of external lubricant.

5. The order of hot mixing, temperature setting and curing time are also decisive factors for the performance of the profile.

3. The extrusion process is unreasonable

1. Excessive or insufficient plasticization of materials.

2. Insufficient head pressure.

3. The low molecular components in the product are not discharged.

4. The screw torque is too low.

5. The traction speed does not match the extrusion speed.