1, the needle should have strong toughness: The working […]
1, the needle should have strong toughness:
The working conditions of the needle in the mold are very bad, and often have to bear a huge impact force, so it is easy to break. Therefore, in order to prevent the mold insert from suddenly breaking during work, the insert must have high strength and toughness. The toughness of the needle is mainly determined by the carbon content, grain size and texture of the material, so the selection of the needle is very important.
2, the needle should have wear resistance:
When the needle is plastically denatured in the cavity of the mold, it continuously slides along the surface of the cavity, and a huge frictional force is generated between the surface of the cavity and the insert, and the insert is very easy to wear. Therefore, the material for manufacturing the needle should have strong wear resistance, which is one of the most basic and important performances of the needle. The hardness of the material is also the main factor affecting the wear resistance. Generally speaking, the higher the hardness of the insert, the smaller the wear and the better the wear resistance. In addition, the wear resistance of the insert is also related to the chemical and physical form of the carbide in the material.
3, the needle should have anti-fatigue fracture performance:
In the high-strength working process, the needle is used for a long time, which often leads to fatigue fracture. The form has small energy multiple impact fatigue fracture, tensile fatigue fracture contact fatigue fracture and bending fatigue fracture. The fatigue fracture properties of the inserts are mainly determined by their strength, toughness, hardness, and the amount of inclusions in the material. Therefore, the manufacturer of the inserts should be made of high quality materials, preferably imported materials.
Therefore, in the processing of the needle to pay more attention to meet the above requirements, in order to make the needle play the most important role in the mold.