There are more and more applications of abrasive steel. […]
There are more and more applications of abrasive steel. When manufacturing moulds, the mould steel must meet some working conditions, such as hardness, strength, wear resistance and sufficient toughness. Only the working conditions that meet the mould requirements are met. The mould can be used as a tool for the workpiece. Which mould steel performance indicators are those? There are four main points.
1. Machinability The machinability of mould steel mainly includes cutting, grinding, polishing, cold drawing and other workability and forging workability. Most of the mould steels belong to hypereutectoid steel and lysitic steel, and the hot workability and cold workability are not very good. The process parameters of hot working and cold working must be strictly controlled. In recent years, in order to improve the machinability of mould steel, it is easy to cut elements in the mould steel or change the distribution of inclusions in the steel, thereby improving the surface quality of the mould and reducing the wear of the tool.
With the development of electronic technology, the extensive use of CNC machine tools and machining centers and even computer control technology, mould steel should have good mirror-cutting performance, electrical processing performance and embossing over-die processing. Performance, etc.
2. Hardenability and hardenability The hardenability depends mainly on the carbon content of the die steel. The hardenability depends mainly on the chemical composition of the die steel and the original structure of the steel before quenching. The requirements of these two properties of the mould are different according to their service conditions. For moulds that require uniform performance across the entire section, such as hot work moulds and plastic moulds, high hardenability is more important; Small cold work dies with high hardness, such as blanking dies, are more focused on high hardenability.
3. Quenching temperature and heat treatment deformation In order to facilitate the production, the quenching temperature range of the mould steel is required to be as wide as possible, especially when the mould is partially quenched by flame heating, the mould steel is required to have a wider quenching temperature range. Except for some moulds made of pre-hardened steel, most of the moulds are heat treated to obtain the desired structure and properties after cutting. Therefore, it is required that the dimensional change during quenching is small, the orientation changes approximately, and the structure is stable.
4. When the decarburization sensitive mould steel is heated in an unprotected atmosphere during forging, annealing or bonfire, the surface layer will have defects such as decarburization, and the durability of the mould will be lowered. The decarburization sensitivity depends mainly on the chemical composition of the mould steel, especially the carbon content.