Forging the forging is the use of a mechanical pressure is applied to the metal blank, so that it is plastically deformed to obtain a certain mechanical properties, shape and size of the forging certain processing methods. Forging one of the components of the two. Eliminate metal by forging cast loose, mechanical welding holes, general superior of the same material forgings castings. Mechanical load is high, the important parts grim working conditions, in addition to simple shapes available rolled sheet, profiles or welded parts, the use of forgings. Forging press forming method can be divided into: ① open forging (free forging). The use of impact or pressure in the upper and lower metal deformation arrived iron (anvil) to obtain the desired forging between, there are two kinds of hand-forged wrought and machinery. ② closed mode forging. The metal blank within the die bore has a shape obtained by forging of compressive deformation, can be divided into forging, cold forging, rotary forging, extrusion and the like. Press forging can be divided into hot forging deformation temperature (processing temperature higher than the recrystallization temperature of the metal billet), warm forging (below the recrystallization temperature) and Cold (normal temperature). Forging materials mainly carbon steel and alloy steel of various components, followed by aluminum, magnesium, titanium, copper and its alloys. The original state of the material has bars, ingots, metal powder and liquid metals. In the cross-sectional area of the metal before deformation ratio of the deformed area of the die-off is called forging ratio. The correct choice of forging ratio to improve product quality, reduce costs a great relationship.
Casting is the metal smelting meet certain requirements in liquid and poured into the mold, the cooling and solidification, the Qing get a predetermined shape, size and performance of castings (parts or blank) after the whole process of treatment. Basic technology of modern machinery manufacturing industry. Rough casting low cost of production, for complex shapes, especially those with complex cavity parts, can show its economy; while its wide adaptability, and has good mechanical properties. But the required casting materials (such as metal, wood, fuel, modeling materials, etc.) and equipment (such as metallurgical furnaces, Mixer, molding machine, core making machine, shakeout machine, shot blasting machine, cast iron plate, etc.) than and more, and will generate dust, harmful gases and noise pollution. Casting earlier human grasp a metal thermal processing, about 6,000 years old. 3200 BC, Mesopotamia appear copper frog castings. BC between 13 to 10 centuries ago, China has entered the heyday of bronze casting, the process has reached a very high level, such as Shang weight 875 kg of Simuwu Fangding Warring States of Marquis Yi statue plate and the Western Han Dynasty translucent mirror, etc. are representative of ancient casting products. Early casting greatly influenced pottery, cast mostly for agricultural production, religion, life and other aspects of the tool or appliance, art color darker. In 513 BC, Chinese cast out of the world's oldest written records found in iron castings - casting Jin Ding (about 270 kg weight). Around the 8th century, Europe began producing iron castings. After the Industrial Revolution of the 18th century, cast into the new era of large industrial services. In the 20th century, the development of fast-speed casting, has developed a ductile iron, malleable iron, low carbon stainless steel and aluminum copper, aluminum silicon, aluminum-magnesium alloys, titanium-based, nickel-based alloys, such as casting metal material, and the invention of gray cast iron inoculation of new technology. After the 1950s, the emergence of new high-pressure molding process of wet sand, chemical hardening sand molding and core making, molding and other special vacuum casting, shot blasting, etc. Casting many types, according to the modeling method used to be divided into: ① ordinary sand casting, including wet sand, dry sand and chemical hardening sand three categories. ② special casting, press molding material can be divided into natural mineral sand as the main form of special casting material (such as investment casting, mud casting, foundry shell casting, vacuum casting, solid casting, ceramic casting etc.) and metal as the main material of special casting mold (such as metal casting, pressure casting, continuous casting, low pressure casting, centrifugal casting, etc.) categories. Casting process typically includes: ① mold (the liquid becomes solid cast metal containers) prepared according to the materials can be cast into sand, metal, ceramic, clay type, graphite, etc., according to the frequency of use can be divided into a sex, semi-permanent and permanent, mold preparation of the merits of the main factors affecting the quality of castings; ② cast metal melting and pouring, casting metal (cast alloy) are mainly iron, steel and non-ferrous alloy casting; ③ casting treatment and testing, including the removal of casting processing core and the casting surface foreign matter removal riser, grinding burrs and Phi joints and other projections as well as heat treatment, shaping, anti-rust treatment and rough and so on.
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