The Pail Mould material selection requirements and standards, this is the necessary design knowledge of bucket molds manufacturers and bucket molds designers. These requirements and standards play a crucial role in the performance of the bucket molds.
First, the choice of bucket mold material must meet the working conditions
1, the bucket mold steel must have high temperature resistance
When the working temperature of the bucket mold is higher, the hardness and strength are lowered, resulting in early wear of the bucket mold or plastic deformation and failure. Therefore, the mold steel should have high anti-tempering stability to ensure that the mold has high hardness and strength at the working temperature.
2, the bucket mold steel must have corrosion resistance
Some bucket molds, such as plastic molds, when working, due to the presence of chlorine, fluorine and other elements in the plastic, after the heat, the HCI, HF and other strong aggressive gases are resolved, eroding the surface of the bucket mold cavity, increasing its surface roughness and aggravating wear and tear.
3, the bucket mold steel must have wear resistance
When the blank is plastically denatured in the bucket mold cavity, it flows and slides along the surface of the cavity, causing severe friction between the surface of the cavity 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 a major factor affecting wear resistance. In general, the higher the hardness of the mold part, the smaller the wear amount, and the better the wear resistance. In addition, the wear resistance is also related to the type, quantity, shape, size and distribution of carbides in the material.
4, the bucket mold steel must have resistance to cold and heat fatigue
Some bucket molds are in a state of repeated heating and cooling during the working process, causing the surface of the cavity to be subjected to tensile and pressure-induced stress, causing surface cracking and spalling, increasing friction, impeding Plastic Bucket Mould deformation, and reducing dimensional accuracy, thereby resulting in The mold failed. Hot and cold fatigue is one of the main forms of hot work die failure, and it should have high resistance to cold and heat fatigue.
5, the bucket mold steel must have fatigue fracture properties
During the working process of the bucket mold, under the long-term action of the cyclic stress, fatigue fracture is often caused. 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 mold depend mainly on its strength, toughness, hardness, and the amount of inclusions in the material.
6, the bucket mold material must have toughness
Most of the working conditions of the bucket mold are very bad, and some often suffer from a large impact load, resulting in brittle fracture. In order to prevent the mold parts from suddenly breaking during work, the bucket mold must have high strength and toughness. The toughness of the mold depends mainly on the carbon content, grain size and microstructure of the material.
Second, the mold steel must meet the process performance requirements
Mold manufacturing generally involves several processes such as forging, cutting, and heat treatment. In order to ensure the quality of the bucket mold and reduce the production cost, the material should have good forgeability, machinability, hardenability, hardenability and grindability; it should also have small oxidation, decarburization sensitivity and quenching. Deformation cracking tendency.
1. Machinability, large cutting amount, low loss, and low surface roughness.
2. Annealing processability, wide spheroidizing annealing temperature range, low annealing hardness, small fluctuation range and high spheroidization rate.
3, forgeability, low hot forging deformation resistance, good plasticity, wide forging temperature range, cold cracking of forging cracks and low tendency to precipitate reticular carbides.