As a key basic process in equipment manufacturing, heat treatment plays an irreplaceable core role in improving the performance of mechanical and electrical products, prolonging service life, and improving market competitiveness. Among them, high-frequency quenching heat treatment, as an advanced technology, uses high-frequency current to heat and cool the surface of the workpiece locally, so as to obtain a surface hardening layer, which has become one of the prominent applications. Let's take an in-depth look at the difference between high-frequency heat treatment and ordinary heat treatment and the high-frequency quenching process.
Differences and areas of application.
The approach is different. High-frequency quenching: Through rapid heating, the surface is brought to the quenching temperature, and then it is cooled quickly. This hardens the surface to martensite while maintaining the plasticity and toughness of the central part.
Ordinary quenching: After the metal workpiece is heated to a suitable temperature, it is quickly immersed in the quenching medium to achieve metal heat treatment through rapid cooling.
The application is different. High-frequency quenching: It is suitable for workpieces subjected to alternating loads such as torsion and bending, and requires high surface stress or wear resistance. It is especially suitable for steels with a high carbon content.
Ordinary quenching: Widely used in modern machinery manufacturing, almost all key mechanical parts need to be quenched.
Again, the material processing results are different.
High-frequency quenching: Hardens the surface layer, but keeps the center relatively soft. The surface hardness is higher than that of the center.
Normal quenching: Increases the overall hardness and hardens both the surface and the center.
Analysis of high-frequency quenching process.
The high-frequency quenching process consists of several critical steps, each of which has a significant impact on the quality of the final product.
Preheating: The workpiece is preheated, and the control and regulation of the preheating temperature is crucial.
Heat treatment: The surface of the workpiece is heated with a high-frequency electric current to bring it to quenching temperature.
Cooling: Quickly cools the workpiece to form a case-hardened layer.
Annealing: Relieves quenching stress and maintains the overall properties of the material.
Tempering: Further adjustment of the hardness to improve the toughness of the material.
Inspection: Quality inspection of the quenching area to ensure conformity.
Packing, Shipping, Selling: Packaging and placing the final product on the market.
High-frequency quenching principle and heating temperature requirements.
The principle of high-frequency quenching is based on electromagnetic induction, which generates heat inside the workpiece to achieve cooling and quenching after heating. The heating temperature is generally required to be about 800, considering the high frequency heating speed, it is necessary to make the austenitization sufficient. The increase in temperature also contributes to the full dissolution of alloying elements in austenite, improving the uniformity of hardenability and mechanical properties.
Inductor design and quenching media selection.
The design of the inductor should be determined according to the size of the high-frequency quenching zone, which is usually slightly smaller than the quenching zone and similar in shape to the workpiece. The choice of quenching medium is crucial in high-frequency processes, and water-based quenching fluids are often used to avoid the development of quenching microcracks.
Tempering after quenching.
In order to eliminate quenching stress, timely tempering is required after high-frequency quenching. The tempering temperature is generally about 180, and the tempering time should be sufficient, usually more than 90 minutes.
In summary, there are significant differences between high-frequency heat treatment and ordinary heat treatment in terms of method, application, and treatment results. The high-frequency quenching process is complex and requires precise control of all aspects to ensure that the final product meets the design requirements. Through an in-depth understanding of the principle of high-frequency quenching, heating temperature, inductor design, etc., the technology can be better applied, improve production efficiency and product quality, and promote the continuous innovation of the equipment manufacturing industry.