Processing and forming methods and production processes of aluminum alloy
At present, the production methods of aluminum and aluminum alloy mainly include casting method, plastic forming method and deep processing method. This article mainly discusses the plastic forming method of deformed aluminum alloy.
Classification and characteristics of plastic processing and forming methods of aluminum alloy.
There are many plastic processing and forming methods for aluminum and aluminum alloys, and the classification standards are not uniform. At present, the most common classification is based on the temperature characteristics of the workpiece during processing and the stress-strain state of the workpiece during the deformation process.
1) Classification according to temperature characteristics during processing
According to the temperature characteristics of the workpiece during processing, aluminum and aluminum alloy processing methods can be divided into hot processing, cold processing and warm processing.
A hot processing
Hot processing refers to the plastic forming process of aluminum and aluminum alloy ingots above the recrystallization temperature. During hot processing, the plasticity of the ingot is high and the deformation resistance is low. Products with larger deformation can be produced with equipment with smaller tonnage. In order to ensure the structural properties of the product, the heating temperature, deformation temperature and deformation speed, deformation degree, deformation end temperature and cooling rate after deformation of the workpiece should be strictly controlled. Common aluminum alloy hot processing methods include hot extrusion, hot rolling, hot forging, hot upsetting, liquid die forging, semi-solid forming, continuous casting and rolling, continuous casting and extrusion, etc.
B cold processing
Cold processing refers to the plastic forming process completed below the temperature where recovery and recrystallization do not occur. The essence of cold working is a combined process of cold processing and intermediate annealing. Cold processing can produce final products with smooth surfaces, precise dimensions, good structural properties, and can meet different performance requirements. The most common cold processing methods include cold extrusion, cold upsetting, pipe cold rolling, cold drawing, plate, strip and foil cold rolling, cold stamping, cold bending, spinning, etc.
C warm processing
Warm processing refers to the plastic forming process between cold and hot processing. Warm processing is mostly a processing method used to reduce the deformation resistance of metal and improve the plastic properties (processability) of metal. The most common warm processing methods include warm extrusion, warm rolling, warm upsetting, etc.
2) Classification according to the stress-strain state during deformation
According to the force and deformation mode of the workpiece during the deformation process, the processing of aluminum and aluminum alloys can be divided into rolling, extrusion, drawing, forging, spinning, forming processing, and deep processing.
Aluminum and aluminum alloys are produced through smelting and casting. As the blank material for plastic processing, the internal crystal structure of the ingot is coarse and uneven. From the cross section, fine grain bands, columnar grain bands and coarse grains can be seen. axis grain band. The ingot itself has low strength and poor plasticity, and in many cases cannot meet the usage requirements. Therefore, in most cases plastic processing is required to change its shape and size and improve its structure and performance.