1. The difference between forging and casting:
Words have different meanings:
Forging: By hammering and other methods, the metal material in the plastic state becomes a workpiece with certain shape and size, and changes its physical properties.
Casting: The process of melting metal into liquid and pouring it into the mould, cooling, solidifying and cleaning to obtain the required shape of the casting. It can be made into various objects with complex shapes.
2. Different manufacturing processes:
Forging: Forging is a kind of processing method that uses forging machinery to exert pressure on metal blanks to produce plastic deformation to obtain forgings with certain mechanical properties, shape and size. Forging (forging and stamping) is one of the two major components.
Casting: The method of casting liquid metal into a casting cavity suitable for the shape of the part and cooling and solidifying it to obtain the part or blank.
2. Forging and foundry uses:
Forging is generally used in the processing of forgings of certain shapes and sizes.
Casting is a relatively economical method of blank forming, which is generally used on parts with complex shapes.
3. Advantages and disadvantages of forging and casting:
Forging advantages:
Forging can eliminate the defects such as as as as-cast looseness and optimize the micro-structure of metals in the smelting process. At the same time, the mechanical properties of forgings are generally better than those of castings of the same material because of the preservation of complete metal streamlines. Forgings are often used for important parts with high load and severe working conditions in related machinery, except for simple rolled plates, profiles or weldments.
Casting advantages:
It can produce parts with complex shape, especially blanks with complex inner cavity.
2.Wide adaptability, the metal materials commonly used in industry can be cast, several grams to hundreds of tons.
3.Raw materials come from a wide range of sources and are inexpensive, such as scrap, scrap, chips and so on.
4.The shape and size of the castings are very close to the parts, which reduces the amount of cutting and belongs to non-cutting processing.
5.It is widely used. 40%~70% of agricultural machinery and 70%~80% of machine tools are castings.
Defects of forging:
Traumatic accidents are easy to occur in forging production.
Casting defects:
1.Mechanical properties are not as good as forgings, such as coarse structure and many defects.
2.In sand mould casting, single piece, small batch production, worker labor intensity is high.
3.Casting quality is unstable, there are many processes, and the influencing factors are complex. It is easy to produce many defects.
Extended information:
Forging is one of the important methods of metal plastic processing. The main purpose of forging is: forming and modification (improvement of mechanical properties and internal structure). Among them, the latter is difficult to achieve by other process methods. In addition, forging production also has the advantages of saving metal, high production efficiency and flexibility.
Forging can make the casting structure loose, pore compaction, crush the coarse casting structure (dendritic grain) into fine grains, and form fiber structure. When the fibre structure is reasonably distributed along the contour of the part, the mechanical properties of the part can be improved. As a result, forged parts have high strength and can withstand greater impact loads.
Under the same impact load, the size of forged parts can be reduced, that is to say, metal can be saved. For example, the U.S. forged 272 parts and 3200 bolts with 315 MN hydraulic press F-102, which reduced the aircraft mass and replaced 45.5-54.5 kg of the overall beam on the aircraft.
Casting is the manufacturing process of parts with required shape and properties obtained by pouring molten metal liquid into the casting mould and cooling and solidification. Casting is a commonly used manufacturing method. It has low manufacturing cost and great flexibility. It can obtain complex shape and large castings. It occupies a large proportion in mechanical manufacturing, such as machine tools 60-80%, automobiles 25%, tractors 50-60%.
Due to the improvement of casting quality, casting precision, casting cost and automation, casting technology is developing towards precision, large-scale, high-quality, automation and cleanliness, such as precision casting technology, continuous casting technology, special casting technology, casting automation and casting technology in recent years in China. The technology of causative simulation has developed rapidly.