The hottest multi parameter heat treatment and com

2022-08-24
  • Detail

Multi parameter heat treatment and composite heat treatment process

heat treatment is an important basic technology in the machinery industry. Usually, important mechanical parts and tools and dies such as shafts, bearings, gears, connecting rods and so on need heat treatment. Moreover, as long as the material selection is appropriate and the heat treatment is appropriate, the service life of mechanical parts and tools and dies can be doubled, or even more than ten times, to achieve the goal of doing a good job in heat treatment and top several parts, Get twice the result with half the effort

in terms of the main control parameters of traditional heat treatment, most of them are heat treatment with two parameters of temperature and time under normal pressure; In terms of process mode, most of them are single heat treatment. In this way, the effect of heat treatment can only be simplified. Therefore, we should vigorously develop multi parameter heat treatment and composite heat treatment processes

multi parameter heat treatment

vacuum heat treatment: This is a multi parameter heat treatment with additional pressure. It has the advantages of no oxidation, no decarburization, bright workpiece surface, small deformation, no pollution, energy saving, high automation and wide application range. It is one of the fastest-growing new heat treatment technologies in recent years, especially in the surface modification of materials. Many newly developed advanced heat treatment technologies, such as vacuum high-pressure gas quenching and vacuum chemical heat treatment, also need to be implemented under vacuum. The use of vacuum heat treatment technology can greatly improve the quality and service life of structural materials, tools and dies, which is especially suitable for some precision companies to explore new technology paths, including solid-state batteries, such as heat treatment of dense parts. In the industrial developed countries, the proportion of vacuum heat treatment has reached about 20%, while China currently has about 1200 vacuum heat treatment furnaces, accounting for about 1% of the total number of heat treatment furnaces, which is far from foreign countries. It is expected that in the future, with the technological progress of the heat treatment industry and the higher and higher requirements for the quality of heat treated workpieces, vacuum heat treatment will have greater development

chemical heat treatment: This is a multi parameter heat treatment with additional components. Common chemical heat treatment, such as carburizing, carbonitriding, carbonitriding and boronizing, belong to multi parameter heat treatment with additional single component, double component and three component respectively. In recent years, many new chemical heat treatments using new technologies have been developed, such as vacuum chemical heat treatment, fluidized bed chemical heat treatment, ion metallization, ion implantation, laser surface alloying, etc., which can improve the wear resistance and corrosion resistance of workpieces. The application of rare earth in chemical heat treatment (i.e. co infiltration with rare earth) can significantly improve the infiltration rate, shorten the treatment cycle, and improve the wear resistance and corrosion resistance of the infiltration layer, which is a major feature of our country. In addition, solution chemical heat treatment is also a trend worthy of attention. Huang Jianhong of Inner Mongolia Agricultural Machinery Research Institute and others developed the nitrogen-containing martensite treatment (n*m treatment), which is the first nitriding process for the purpose of obtaining nitrogen-containing martensite of solid solution N, and has been successfully applied to the production of Shearer blades

(3) thermomechanical treatment: This is a multi parameter heat treatment with additional stress. The combination of pressure processing and heat treatment combines deformation strengthening and phase transformation strengthening, so that the material can achieve the dual purpose of molding and composite strengthening. Thermomechanical treatment can improve the comprehensive mechanical properties of materials, simplify the process, use waste heat, save energy and material consumption, and achieve remarkable economic benefits. Thermomechanical treatment is widely used, from structural steel, bearing steel to high-speed steel. At present, forging waste heat quenching and controlled rolling are the most widely used in industry. The United States adopts controlled rolling to produce high hardness armor steel plates, which can improve the ballistic performance. The ordnance industry system of our country has carried out experimental research on hot die forging waste heat quenching of artillery and shell parts, rotary precision forging deformation heat treatment of gun barrel, cross rolling waste heat quenching of gun steel core, and achieved good results

composite heat treatment

composite heat treatment is the combination of two or more heat treatment processes, or the combination of heat treatment and other processing processes. In this way, the comprehensive effect of several processes involved in the combination can be obtained, so that the workpiece can obtain excellent performance, save energy, reduce costs, and improve production efficiency. Such as the combination of nitriding and high-frequency quenching, quenching and sulfurizing, boriding and powder metallurgy sintering process. The above-mentioned forging waste heat quenching and controlled rolling also belong to composite heat treatment, which are respectively the combination of forging and heat treatment, and the combination of rolling drum stripping experimental system and heat treatment. There are also some new composite surface treatment technologies, such as laser heating and chemical vapor deposition (CVD), ion implantation and physical vapor deposition (PVD), physical chemical vapor deposition (PCVD), etc., which have significant surface modification effects, mainly through environmental protection materials, ultra light earth and 3D printing, and their applications are also increasing at home and abroad

it should be pointed out that composite heat treatment is not a simple superposition of several single heat treatment processes, but should be organically combined according to the requirements of the performance of the workpiece and the characteristics of each heat treatment process, so as to achieve the purpose of learning from each other and complement each other. For example, due to the different treatment temperatures of various heat treatment processes, it is necessary to consider the sequence of heat treatment processes participating in the combination, so as to avoid the offset effect of the subsequent process on the previous process

heat treatment is a frequently used experimental method for studying material properties. It is of great significance to give full play to the performance potential of metal materials, improve the internal quality of products, save materials, reduce energy consumption, prolong the service life of products, and improve economic benefits

Copyright © 2011 JIN SHI