一 、Structural changes
When the general aluminum enclosure is cold, the material structure changes, so that the material hair quality, performance anisotropy, may lose the original characteristics or abnormal changes. At this time, we can only reduce the probability of abnormal changes and guide them to develop in their own favorable direction.
二 、Influence physical and chemical properties
1. Low temperature will destroy the chemical structure of the aluminum profile enclosure, produce chemical reactions, destroy the original covalent bonds, and corrode the aluminum enclosure.
2. Damage the physical structure of aluminum enclosures because they are processed for long periods at low temperatures, resulting in density changes and fine damage.
3. Intergranular material is destroyed, resulting in disordered grain arrangement.
三 、Lead to processing embrittlement
When the aluminum enclosure changes, it will lead to the destruction of the crystal, the change of the lattice, the sharp decline in its own plasticity index, the aluminum enclosure becomes very brittle when in use, easy to deformation.
Temperature has a great influence on the surface quality of extruded profiles, so it is necessary to strictly control the temperature of each process, including the temperature and the temperature rise caused by friction during extrusion, the temperature of the ingot bucket, the temperature of the mold, the temperature of the aluminum rod and the temperature of the heat treatment.