Mold Heat Treatment Technology Status and Trend
Die mold heat treatment is to ensure that the performance of an important process for the manufacture of precision molds, mold strength, the working life of die and mold manufacturing costs have a direct impact. Since the 20th century, 80 years, the international mold heat treatment technology, a fast-growing area of vacuum heat treatment technology, the mold surface strengthening technology and pre-hardened mold material technology.
Mold Vacuum Heat Treatment Technology
Vacuum heat treatment technology is developed in recent years a new type of heat treatment technology, it has the characteristics, it is urgently needed in mold manufacturing, such as to prevent oxidation and non-decarbonization heat, vacuum degassing or outgassing, eliminating hydrogen embrittlement, thereby enhancing material (parts) of the plasticity, toughness and fatigue strength. Vacuum heating is slow, spare parts a smaller temperature difference between inside and outside factors such as the decision of the vacuum heat treatment process caused by deformation of parts and small.
Mold vacuum heat treatment is the main application of the vacuum oil-cooling quenching, vacuum-cooled quenching and vacuum annealing. In order to maintain the workpiece (eg, mold) of the superior characteristics of vacuum heating, cooling agent and the cooling process of selection and development is very important, die quenching process is mainly used oil-cooling and air-cooled. For the heat treatment carried out after the machining of the mold is no longer face, vacuum annealing after quenching as far as possible, especially in the vacuum hardening of the workpiece (mold), which can improve the mechanical and surface quality-related properties, such as fatigue properties, surface brightness, corrosion resistance and so on.
Heat treatment process, the success of computer simulation technology development and application of intelligent heat treatment makes it possible to die. As the mold of small quantities (or even a single piece), multiple varieties of features, and performance requirements for heat treatment of high and does not allow for the characteristics of waste, but also makes intelligent mold heat treatment is a must. Western industrial countries, such as the United States, Japan, in a vacuum high pressure gas quenching, the development soon, the main target is also a mold.
Mold Surface Treatment Technology
Mold in the work required in addition to the matrix with a sufficiently high strength and toughness of the reasonable co-ordination, the surface performance of the work performance and service life of dies is essential. Die surface treatment technology, through the surface coating, surface modification or composite processing technology to change the mold surface morphology, chemical composition, organizational structure and stress state in order to obtain the required surface properties of systems engineering. At present the application of more in the mold manufacturing is mainly nitriding, carburizing, and hardening of film deposition.
As the nitriding technology can be developed into a fine performance of the surface, and the nitriding process and die steel quenching processes are well coordinated, while low temperature nitriding, nitriding without heated after cooling, a very small deformation of the mold, so mold nitriding surface hardening technology is used earlier, but also the most widely used.
Mold carburizing is to enhance the overall strength and toughness of the mold, that mold working surface with high strength and wear resistance. Hardened film deposition technology is currently more mature is the CVD, PVD. Mold 80 years since the last century began to use hardened coating film technology. The current technological conditions, the hardened film deposition technologies (mainly equipment) costs are higher, still only in a number of sophisticated, long-life die on the application, if we adopt the way of the establishment of heat-treatment center, then coated with hardened film would greatly reduce the cost of more die if we adopt this technology, you can mold the overall improvement of China's manufacturing standards.
The pre-hardened mold material technology
70 years since the last century began, the international community put forward the idea of pre-hardened, but because of machine tool and cutting tool rigidity constraints, pre-hardened mold hardness can not be used to achieve hardness, so the pre-hardened technology, R & D investment is not. As the machine tool and cutting tools enhance the performance of the pre-hardened mold material accelerated technology development, to the last century 80's, the international timber industry developed countries in the plastic mold using the ratio of pre-hardened module has reached 30% (currently 60% above).
China in the pre-hardened mold material technology, started late, small-scale, we can not meet the domestic mold manufacturing requirements. Use of pre-hardened mold material, mold manufacturing process can simplify and shorten the manufacturing cycle of molds, improve the manufacture of precision molds. It can be predicted, with the advances in processing technology, pre-hardened mold material will be used for more types of mold
This information comes from [ Wishsino Plastic Mold making Company Website.]
