- The mold meets the requirements of working conditions What kind of material can make a good mold?
- Wear resistance
When the blank is plastically deformed in the mold cavity, it flows and slides along the surface of the cavity, causing severe friction between the cavity surface and the blank, which causes the mold to fail due to wear. Therefore, the wear resistance of the material is one of the most basic and important properties of the mold.
Hardness is the main factor affecting wear resistance. Generally speaking, the higher the hardness of the mold parts, the smaller the wear and the better the wear resistance. In addition, wear resistance is also related to the type, quantity, shape, size and distribution of carbides in the material.
- Strength and toughness
Most of the working conditions of the mold are very bad, and some often bear large impact loads, which leads to brittle fracture. In order to prevent the mold parts from suddenly breaking during operation, the mold must have high strength and toughness.
The toughness of the mold mainly depends on the carbon content, grain size and organizational state of the material.
- Fatigue fracture performance
During the working process of the mold, fatigue fracture is often caused under the long-term action of cyclic stress. Its forms include small energy multiple impact fatigue fracture, tensile fatigue fracture, contact fatigue fracture and bending fatigue fracture.
The fatigue fracture performance of the mold mainly depends on its strength, toughness, hardness, and the content of inclusions in the material.
- High temperature performance
When the working temperature of the mold is high, the hardness and strength will decrease, resulting in early wear or plastic deformation of the mold and failure. Because the mold material should have a high anti-tempering stability to ensure that the mold has a high hardness and strength at the working temperature. - Cold and hot fatigue resistance
Some molds are in a state of repeated heating and cooling during the working process, so that the surface of the cavity is subjected to tension, pressure and variable stress, causing surface cracking and peeling, increasing friction, hindering plastic deformation, and reducing dimensional accuracy, thereby causing mold failure. Cold and hot fatigue is one of the main forms of failure of hot working molds. This type of mold should have a high resistance to cold and hot fatigue. - Corrosion resistance
When some molds, such as plastic molds, are working, due to the presence of chlorine, fluorine and other elements in the plastic, after heating, they will decompose and precipitate highly corrosive gases such as HCI and HF, which will corrode the surface of the mold cavity, increase its surface roughness, and aggravate wear and failure. - The mold meets the process performance requirements
The manufacturing of the mold generally requires several processes such as forging, cutting, and heat treatment. In order to ensure the manufacturing quality of the mold and reduce production costs, its material should have good forgeability, cutting processability, hardenability, hardenability and grindability; it should also have low oxidation, decarburization sensitivity and quenching deformation cracking tendency.https://solidcomould.com/product-category/injection-mould/electric-box-mould-2/
- Forgeability
It has low hot forging deformation resistance, good plasticity, wide forging temperature range, low tendency of forging cracking, cold cracking and precipitation of network carbides. - Annealing processability
The spheroidizing annealing temperature range is wide, the annealing hardness is low and the fluctuation range is small, and the spheroidization rate is high. - Cutting processability
The cutting amount is large, the tool loss is low, and the surface roughness of the machined surface is low. - Oxidation and decarburization sensitivity
When heated at high temperature, it has good oxidation resistance, slow decarburization speed, is insensitive to the heating medium, and has a low tendency to produce pitting. - Hardenability
After quenching, it has a uniform and high surface hardness. - Hardenability
After quenching, a deeper hardened layer can be obtained, and it can be hardened using a mild quenching medium. - Quenching deformation and cracking tendency
The volume change of conventional quenching is small, the shape warping and distortion are slight, and the tendency of abnormal deformation is low. Conventional quenching has low cracking sensitivity and is insensitive to quenching temperature and workpiece shape. - Grindability
The grinding wheel has a small relative loss, a large grinding amount without burning limit, is insensitive to the quality of the grinding wheel and cooling conditions, and is not prone to grinding and grinding cracks. - The mold meets the economic requirements
When selecting materials for the mold, the principle of economy must be considered to reduce the manufacturing cost as much as possible. Therefore, under the premise of satisfying the performance, the first choice is the one with lower price. Carbon steel should be used instead of alloy steel, and domestic materials should be used instead of imported materials. In addition, the production and supply situation of the market should also be considered when selecting materials. The selected steel types should be as few and concentrated as possible and easy to purchase.https://solidcomould.com/product-category/injection-mould/gardening-product-mold-2/
