Q:What is normalizing, annealing, tempering, quenching? What is the difference between forging parts and casting parts?

The aim is to make the grain fine and distribute the carbide evenly. The difference between normalizing and annealing is that normalizing cooling rate is slightly faster than annealing cooling rate, so normalizing structure is finer than annealing structure, and its mechanical properties are also improved. In addition, normalizing furnace cooling does not occupy equipment and has higher productivity. Therefore, normalizing may be used instead of annealing as much as possible. The main application areas of normalizing are as follows: for low carbon steel, after normalizing, the hardness is slightly higher than that of annealing, and the toughness is better. It can be used as the pretreatment of cutting. Used for medium carbon steel, instead of quenching and tempering, as the final heat treatment, or as an induction heating method before surface hardening. Used for tool steel, bearing steel, carburizing steel, etc., it can eliminate or restrain the formation of network carbide, so as to obtain the good organization of spheroidizing annealing. For cast steel, the microstructure can be refined and the machinability can be improved. Used for large forgings, which can be used as final heat treatment, so as to avoid larger cracking tendency during quenching.

Q:Explain the heat treatment effect of casting parts, forging parts and welding parts

The three methods of metal processing have one thing in common. They are hot working, which are different in temperature and range of processing. Ductile cast iron is widely used because of its brittleness and poor impact. Heat treatment of cast iron usually adopts the annealing process, reduce the casting effect: 1 because of the internal stress caused by the thermal expansion and contraction, reduce the deformation after machining, decrease surface hardness, improve machining conditions;

Q:Does anyone know how to make precise casting parts for aerospace or manufacturers of single and small quantities of automotive parts and components, mainly in Beijing, Tianjin and Tangshan?

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Q:our factory now produces steel castings in the use of polishing directly after spraying processing, but the powder sprayed 15But the spray powder touched off what is the reason we are not very strict requirements not only need to peel off bubbles can also, because our products are steel castings so we use steam hole sludge put on. Do not know if this spray treatment has no effect to thank friends with us!

Steel parts are not familiar. But after spraying, the powder should be divorced from the adhesive force is too low, try to provide the surface roughness of the casting

Q:Younger brother is to do casting valve, precision casting parts, the valve internal sand serious, but the appearance is very standard, this is why, for God answers, thank you!

If is casting, internal shell mold may be not completely dry, strength is not enough, resulting in shell mold collapse into molten steel.It is also possible that the refractory is not refractory enough.

Q:What are the effects of stiffeners on castings, or on welded parts (for 2 tons or less), casting or weldments on stiffeners?

3, weight: if reinforcement in products, casting weight is generally greater than the welding parts (the internal organizational structure and mode of production determines the mechanical properties of materials, so it determines the weight of the product), considering the cost of transportation, certain priority structure.

Q:How can the casting be quenched and tempered?

Return, general castings (especially steel castings) commonly used heat treatment process is normalized and tempered. Of course there are completely by annealing or remove stress annealing...

Q:I often see Waixiejiagong drawings, casting, how to distinguish the latheman.

The technical condition or the material column in the title column will tell whether it is a casting drawing or not. However, the need for casting drawings, and some also through machining (car, milling, etc.), this should be part of the process drawings, process drawings are described

Q:What are the general technical requirements for casting parts?

No matter what kind of material casting, there are the following major requirements:Material requirements. Mainly hardness, tensile strength, elongation, impact toughness.Two, dimensional accuracy and shape accuracy. Different castings have different requirements. Different sizes and geometric tolerances and different tolerances are adopted.Three, according to the use requirements, the casting of other defects, acceptance requirements. Such as holes, sand holes, shrinkage, slag, sand, crack.........Four. Requirements for defect repair.

Q:What's the cause of the choking of the casting?,

2. when casting mold exhaust condition is not good, in the casting material use consider whether and hinder its gas permeability; in the process to consider to release more pores, multi venting; core exhaust is particularly important.