Rolling is a plastic deformation process in which an ingot is pulled into a rotating roll by friction, and the cross-section is reduced by the pressure applied by the roll, the shape is changed, the thickness is thinned, and the length is increased. According to the different rotation directions of the rolls, the rolling can be divided into vertical rolling, cross rolling and cross rolling. In the longitudinal rolling, the working rolls rotate in the opposite direction, and the longitudinal axis of the rolling stock is perpendicular to the axis of the rolls. It is the most common method for rolling aluminum alloy sheets, strips and foils. When rolling, the working rolls are The direction of rotation is the same, the longitudinal axis of the rolling stock is parallel to the axis of the roll, and is rarely used in the strip rolling of aluminum alloy sheets; in the case of cross-rolling, the direction of rotation of the work rolls is the same, and the longitudinal axis of the rolled piece is constant with the axis of the roll. slope. Two-roll or multi-roll cross-rolling is commonly used in the production of aluminum alloy pipes and certain shaped products. Depending on the roll system, aluminum alloy rolling can be divided into two rolls (one pair) rolling, multi roll rolling and special roll (such as planetary rolling, V rolling, etc.) rolling. Depending on the shape of the rolls, aluminum alloy rolling can be divided into flat roll rolling and hole roll rolling. According to different product varieties, aluminum alloy rolling can be divided into plate, belt and foil rolling, bar, flat bar and profiled profile rolling, pipe and hollow profile rolling.
Extrusion is a method in which an ingot is placed in a squeeze cylinder, and a metal is pressed by an extrusion shaft to be pressed from a die hole of a given shape and size to cause plastic deformation to obtain a desired extruded product. processing method. According to the different metal flow directions during extrusion, the extrusion can be divided into forward extrusion, reverse extrusion and co-extrusion. In the forward extrusion, the direction of movement of the extrusion shaft coincides with the flow direction of the extruded metal, and in the direction of the reverse extrusion, the direction of movement of the extrusion shaft is opposite to the flow direction of the extruded metal. According to the heating temperature of the ingot, the extrusion can be divided into hot extrusion and cold extrusion. Hot extrusion is performed by heating the ingot to a temperature above the recrystallization temperature, and the cold extrusion is performed at room temperature.
Pulling is a stretching machine (or drawing machine) that pulls aluminum and aluminum alloy billets (wires or tube blanks) from a die hole of a given shape and size through a clamp to plastically deform it. Pipe, rod, type, wire processing methods. According to the variety and shape of the products produced, the stretching can be divided into wire stretching, pipe stretching, bar stretching and profile stretching. Tube stretching can be divided into empty drawing, core drawing and flow core stretching. The main elements of the drawing process are a stretching machine, a stretching die and a stretching roll. According to the stretch sizing, the stretching can be divided into single mode stretching and multi mode stretching.
Forging is a processing method in which a forging hammer or a press (mechanical or hydraulic) applies pressure to an aluminum or aluminum alloy ingot or forge by a hammer or an indenter to plastically deform the metal. Aluminum alloy forging has two basic methods: free forging and die forging. Free forging is to forge a workpiece between flat anvils (or anvils); die forging is to place the workpiece in a mold of a given size and shape, and then apply pressure to the workpiece for forging deformation to obtain the required die forging .
(5) Other plastic forming methods of aluminum materials
At present, people have also researched and developed a variety of new aluminum processing methods, which are mainly
a. Pressure casting forming methods, such as low, medium and high pressure forming, extrusion forming, and the like.
b. Semi-solid forming methods, such as semi-solid rolling, semi-solid extrusion, semi-solid drawing, liquid die forging, and the like.
c. Continuous forming method, such as continuous casting and continuous extrusion, high-speed continuous casting and rolling, conform continuous extrusion method, and the like.
d. Composite forming methods such as a lamination rolling method, a multi-blank extrusion method, and the like.
e. Deformation heat treatment method, etc.
Among the aluminum and aluminum alloy processed materials, rolled materials (plates, strips, strips, foils) and extruded materials (tubes, rods, profiles, wires) are the most widely used and the largest output. According to recent statistics, these two types of materials The annual output accounts for 58% and 39% of the world's total annual output of aluminum (average), and the remaining aluminum processed materials, such as forged products, account for only a few percent of the total aluminum production.