What is hot rolling?

Hot rolling generally refers to rolling above the recrystallization temperature of the metal. During the hot rolling process, the metal deformation has both hardening and softening processes. Due to the influence of the deformation speed, as long as the recovery recrystallization process is too late, the metal will have a certain degree of work hardening with the increase of the deformation degree. However, in the hot rolling temperature range, the softening process dominates. Therefore, at the end of hot rolling, the recrystallization of the metal is often incomplete, and the hot-rolled aluminum alloy strip shows a recrystallization and deformation structure.

Features of the hot rolled aluminum sheet

  1. The properties of hot-rolled aluminum sheets in terms of stretching and oxidation are better than those produced by other processes. And the equipment cost and production cost of the hot-rolled sheet is relatively high.
  2. Both cast-rolled and hot-rolled sheets can be used for stretching, but the effect of cast-rolled sheets is not ideal, so the commonly referred to as stretched sheets are generally hot-rolled sheets.
  3. There is also a pre-stretched aluminum plate, which is a relatively hard alloy aluminum plate (there are several grades), which is a process of stretching during the production process, in order to eliminate the internal stress of the aluminum plate and strengthen the flatness.

Hot-rolled-aluminum-sheet-machine

Classification of hot rolled aluminium and aluminum alloys

One is a hot rolled coil

Aluminum and aluminum alloy strips with a thickness of less than 7.0mm from hot-rolled coils are usually produced from hot-rolled coils, and the products are mainly used as cold-rolled billets and sheets. The modern production process is ingot milling → heating (integration of soaking heating) → hot rough rolling → hot continuous rolling → baling and weighing.

The other type is a hot-rolled thick plate

Hot-rolled thick plate refers to aluminum and aluminum alloy plates with a thickness of not less than 7.0mm. The main varieties are hot-rolled plates, annealed plates, quenched or quenched pre-stretched plates, etc. Hot-rolled thick plates are usually produced in hot-rolling mills. The traditional process is: ingot homogenization→milling→heating→hot rolling to cut to length→straightening.

5052 aluminum plate hot rolling temperature

The hot rolling temperature of the 5052 aluminum plate includes the starting rolling temperature and the finishing rolling temperature.

Theoretically, the rolling temperature is 0.85~0.90 times the melting point of the alloy, that is, the solidus temperature, but the influence of the low melting point phase should be considered. If the hot rolling temperature is too high, the coarse grains or the melting of the intergranular low melting point phase are likely to occur, resulting in overheating or overburning of the ingot during heating, and cracking during hot rolling.

The final rolling temperature is generally 20~30℃ above the phase transition temperature. For alloys without phase transformation, the final rolling temperature can be 0.65 to 0.70 times the melting point of the alloy, that is, 65% to 70% of the solidus temperature. To ensure the final rolling temperature, multi-strand continuous rolling is an effective process method.