Forging materials are mainly carbon steel and alloy steel of various components, followed by aluminum, magnesium, copper, titanium and their alloys. Materials in their original state are bars, ingots, metal powder and liquid metal. The ratio of the cross-sectional area of the metal before deformation to the cross-sectional area after deformation is called the forging ratio. Proper selection of forging ratio, reasonable heating temperature and holding time, reasonable initial forging temperature and final forging temperature, reasonable deformation amount and deformation speed have great influence on improving product quality and reducing cost.
Generally, small and medium-sized forgings use round or square bar material as blank. The grain structure and mechanical properties of the bar are uniform and good, the shape and size are accurate, and the surface quality is good, which is convenient for mass production. As long as the heating temperature and deformation conditions are controlled reasonably, the forging with good performance can be produced without large forging deformation.
Ingot is only used for large forgings. Ingot is a cast structure with a large columnar crystal and loose center. Therefore, the columnar crystal must be broken into fine grains through large plastic deformation, and loose compaction, in order to obtain excellent metal structure and mechanical properties.
Powder forging can be made by pressing and firing the preform of powder metallurgy in hot state by die forging without flying edge. The forging powder is close to the density of common die forging parts, has good mechanical properties, and high precision, can reduce the subsequent cutting. Powder forgings have uniform internal structure and no segregation, which can be used to manufacture small gear and other workpieces. But the price of powder is much higher than that of general bar, and its application in production is limited.
By applying static pressure to the liquid metal poured into the die bore, it solidifies, crystallizes, flows, deforms and forms under the action of pressure, the die forging parts of desired shape and performance can be obtained. Liquid metal die forging is a forming method between die casting and die forging. It is especially suitable for complex thin wall parts which are difficult to be formed by common die forging.
In addition to the usual materials for forging, such as carbon steel and alloy steel of various components, followed by aluminum, magnesium, copper, titanium and other alloys, the deformation alloy of iron superalloy, nickel superalloy and cobalt superalloy is also completed by forging or rolling. However, because of the relatively narrow plastic zone of these alloys, the forging difficulty will be relatively large. The heating temperature of different materials, open forging temperature and final forging temperature have strict requirements.
this is open die forging produce by tongxin precision forging company