Mold Steels
Mold steels are an important component of die and mold tools. They involve not only the base material but also a variety of alloy elements to improve its mechanical properties. Mold steels are classified according to the type of steel, such as hot work steel, cold work steel and plastic mold steel.
Hot work steel is characterized by its resistance to high temperatures, such as air cooling and surface hardening steel, and is used to make hot forging and cut dies, hot shearing dies, hot upsetting dies and flanging dies.
Cold work steels are characterized by good wear resistance and toughness. It is used to make cold heading dies, punching dies, cold trimming dies, cold extrusion dies, tamping dies and thread cutting dies.
Plastic mold steel is a steel with good plasticity and moldability. The main elements of plastic mold steel are chromium and molybdenum, and some contain vanadium and tungsten. This kind of steel has good heat resistance, corrosion resistance and high temperature performance, suitable for plastic molds.
Heat treatment of mold steels
Mold steels will go through a series of heat treatment processes before being used as mold core parts. The main processes include tempering, annealing, quenching, normalized, nitrifying and nitrocarburized bright finish.
Tempering is a medium-temperature heat treatment process, which can improve the toughness of the mold core parts and reduce the brittleness.
Annealing is a low temperature heat treatment process by which a metal or alloy that has been rigidly quenched is heated at low temperature and slowly heated and cooled to reduce the hardness and improve the strength.
Quenching is a heat treatment process in which a metal or alloy is heated to a certain temperature and quickly cooled in liquid or gas to increase the hardness of the metal or alloy.
Normalizing is a medium-temperature heat treatment of a metal or alloy, which is heated to the austenite phase and slowly cooled so that its internal structure is uniform.
Nitriding is a hardening process in which nitrogen is added to the surface of a metal or alloy to increase the hardness.
The nitrocarburized bright finish is an electrochemical process for surface hardening of a metal or alloy using nitrates and hydrocarbons.
These various heat treatment processes are used in combination to improve the mechanical properties of the mold.
CAD/CAM and Mold Design
CAD/CAM is used to design and manufacture dies and molds. It is an integration of computer aided design and computer aided engineering. CAD/CAM software is used to represent the geometry of a die or mold and use machining software to convert the geometric model into a program that defines the cutting path of the tool.
CAD/CAM systems are based on 2D models or 3D models, and the geometry is defined using CAD to create the die or mold shape. After the dimensions and dimensions of the model have been established, the cutting tools and other machining operations are simulated using CAM software to generate the CNC codes for the machine tool.
The simulation software used in the die and mold design is 3D simulation software. 3D simulation software is used to reduce the design cycle and optimize the design performance. It allows the designer to visualize the three-dimensional part during design and check how it looks after the machining and assembly are complete, therefore avoiding design errors and improving design efficiency and quality.
Conclusion
The selection of the right mold steel is an important factor in the success of die and mold tool design. A variety of alloy elements are used to optimize the mechanical properties of the steel, and a variety of heat treatment processes are used to improve its hardness, strength and toughness. In order to reduce the design cycle, improve design efficiency and save labor costs, advanced CAD/CAM systems and 3D simulation software are used in the mold design process.
