After forging, the metal can improve its structure and mechanical properties. After hot working and deformation of the casting structure, the original coarse dendrites and columnar grains become fine-grained and uniform-sized equiaxed recrystallized structures due to the deformation and recrystallization of the metal, so that the original segregation, The compaction and welding of looseness, porosity, slag inclusion, etc., the organization becomes tighter, improving the plasticity and mechanical properties of the metal.
Generally speaking, the mechanical properties of castings are lower than those of forgings of the same material. In addition, the forging process can ensure the continuity of the metal fiber structure, make the fiber structure of the forging consistent with the shape of the forging, and the metal flow line is complete, which can ensure that the parts have good mechanical properties and long service life. Precision die forging and cold extrusion , Forgings produced by warm extrusion and other processes are unmatched by castings.
- 1. Aircraft forgings
Calculated by weight, about 85% of the components on the plane are forgings. Aircraft engine turbine disks, rear axle journals (hollow shafts), blades, wing spars, fuselage rib plates, wheel brackets, inner and outer cylinders of landing gear, etc. are all important forgings related to aircraft safety. Aircraft forgings are made of precious materials such as high-strength wear-resistant and corrosion-resistant aluminum alloys, titanium alloys, and nickel-based alloys. In order to save materials and save energy, aircraft forgings are mostly produced by die forging or multi-directional die forging presses. Car forging is calculated by weight, and there are 1719% of forgings on the car. The general automobile is composed of 15 parts such as the body, the trunk, the engine, the front axle, the rear axle, the frame, the gearbox, the transmission shaft, and the steering system. The characteristics of automobile forgings are complex appearance, light weight, poor working conditions, and safety. High standard. Such as crankshafts, connecting rods, camshafts used in automobile engines, front beams required for the front axle, steering knuckles, half shafts used in the rear axle, half shaft bushings, transmission gears in the axle box, etc. Key forgings for the safe operation of automobiles.
- 2. Diesel engine forgings
Diesel engine is a kind of power machinery, it is commonly used as an engine. Take the large diesel engine as an example, the forgings used are cylinder head, main journal, crankshaft end flange output shaft, connecting rod, piston rod, piston head, crosshead pin, crankshaft transmission gear, ring gear, intermediate gear and oil dye pump More than ten kinds of body.
- 3. Marine forgings
Marine forgings are divided into three categories, main engine forgings, shaft forgings and rudder forgings. The main engine forging is the same as the diesel engine forging. Shaft forgings include thrust shaft, intermediate shaft and stern shaft. Rudder system forgings include rudder stock, rudder post, and rudder pin.
- 4. Weapon forgings
Forgings occupy an extremely important position in the weapon industry. By weight, 60% of the tanks are forgings. Barrels, muzzle brakes and breech in artillery, rifled barrels and triangular bayonets in infantry weapons, rocket and submarine deep-water bomb launchers and mounts, stainless steel valves for high-pressure coolers in nuclear submarines, shells Bullets, etc. are all forged products. In addition to steel forgings, weapons are also made of other materials.
- 5. Petrochemical forgings
Forgings are widely used in petrochemical equipment. Such as manholes and flanges of spherical storage tanks, various tube sheets required for heat exchangers, full-forged cylinders (pressure vessels) of butt-welded flange catalytic cracking reactors, cylinder sections used in hydrogenation reactors, and fertilizers The top cover, bottom cover, head, etc. required by the equipment are all forgings.