Metal heat treatment is a crucial step in enhancing material performance. Vacuum furnaces, with their advantages of no oxidation, uniform temperature, and controllable process, play an irreplaceable role in the heat treatment of high-end metal products. The vacuum furnace products of Taicang Huarui Vacuum Furnace Industry Co., Ltd. have accumulated rich application cases in fields such as mold manufacturing, aerospace, and automotive parts by adapting to the characteristics and process requirements of different metal materials. They have demonstrated stable and reliable processing effects and solved many production problems for enterprises.
Vacuum quenching and tempering treatment of die steel
Die steel, as the core material for manufacturing stamping dies, injection molds and other tools, has extremely high requirements for the balance of hardness, toughness and wear resistance. Traditional heat treatment is prone to problems such as oxidation and decarburization, and large deformation. After a large-scale automotive mold enterprise introduced the vacuum oil quenching furnace of Taicang Huarui Vacuum Furnace Industry Co., LTD., it effectively solved these pain points and significantly extended the service life of the molds. The automotive body panel stamping dies produced by this enterprise are made of Cr12MoV die steel. Previously, the salt bath quenching process was used, and a decarburization layer of 0.1-0.2mm often appeared on the die surface, resulting in early wear of the cutting edge and an average service life of only 80,000 times. After switching to the Huarui vacuum oil quenching furnace, the processing flow was optimized as follows: First, heat to 980℃ in a vacuum environment of 5×10⁻²Pa, hold for 2 hours, then quenched in hot oil at 200℃, and finally tempered at 200℃ for 2 hours. The surface of the treated mold is free of oxidation and decarburization, with a hardness of HRC58-60, and the uniformity deviation of hardness is ≤1HRC. More importantly, the slow heating and uniform cooling in a vacuum environment reduce the deformation of the mold. The flatness error of the large covering part mold has been reduced from the original 0.5mm/m to below 0.2mm/m, eliminating the need for subsequent grinding correction processes. Actual usage data shows that the service life of the mold has been extended to over 150,000 times, production efficiency has increased by 40%, and the overall cost has been reduced by 25%. The furnace chamber size customized by Taicang Huarui Vacuum Furnace Industry Co., Ltd. for this enterprise is suitable for large molds. Its double circulation oil circuit design ensures that the cooling rate of all parts of the mold is consistent during quenching, which is the key to stable treatment effect.
Vacuum heat treatment of high-speed steel cutting tools
High-speed steel cutting tools need to have both high hardness and red hardness to meet the wear resistance requirements during high-speed cutting. Traditional box furnace heat treatment is prone to tool chipping due to grain boundary oxidation. After a certain precision tool manufacturer adopted the vacuum quenching furnace of Taicang Huarui Vacuum Furnace Industry Co., LTD., the performance of the tools was significantly improved. The φ10mm high-speed steel end mill produced by this enterprise is made of W6Mo5Cr4V2 material. The previous process had problems such as insufficient hardness of the cutting edge and short service life. After the introduction of the Huarui vacuum quenching furnace, the process was adjusted as follows: under a vacuum degree of 1×10⁻²Pa, the temperature was raised to 850℃ at a rate of 10℃/min, held for 30 minutes, then raised to 1200℃ at a rate of 5℃/min, held for 1 hour, and finally 0.6MPa nitrogen was introduced for cooling. The edge hardness of the milling cutter after vacuum heat treatment reached HRC63-65. The red hardness test showed that after holding at 600℃ for 4 hours, the hardness still remained above HRC58, meeting the requirements of high-speed cutting. The metallographic structure of the cutting tool shows that the grains are uniform and fine, with no grain boundary oxidation phenomenon. This is attributed to the precise temperature control and high-purity nitrogen protection of Huarui vacuum furnace. In the actual cutting test, the feed rate of this milling cutter for processing 45# steel was increased from the original 800mm/min to 1200mm/min. The cutting length of a single tool was extended from 500 meters to 800 meters, and the replacement frequency was reduced, saving a large amount of tool costs for the enterprise
Vacuum annealing treatment of titanium alloy aviation parts
Titanium alloys are widely used in the aerospace field due to their high strength and low density. However, titanium alloy parts are prone to residual stress during processing, which leads to deformation during use. A certain aviation manufacturing enterprise adopted the vacuum annealing furnace of Taicang Huarui Vacuum Furnace Industry Co., Ltd. to treat titanium alloy parts, effectively solving this problem. The TC4 titanium alloy aircraft landing gear connection parts produced by this enterprise have considerable internal stress after machining, and dimensional deviations occur during assembly. The process treated by Huarui vacuum annealing furnace is as follows: under a vacuum degree of 5×10⁻³Pa, the temperature is slowly raised to 700℃, held for 3 hours, and then cooled down to 200℃ with the furnace before being taken out. The residual stress test of the treated parts shows that the stress value has dropped from the original 350MPa to below 80MPa, meeting the requirements of aviation standards. In the subsequent vibration fatigue tests, the fatigue life of the parts was increased from 5,000 cycles to 12,000 cycles, far exceeding the design indicators. More importantly, during the vacuum annealing process, the surface of the parts is free from oxidation, and the roughness is maintained at Ra1.6μm, allowing for direct assembly without the need for secondary processing. The vacuum annealing furnace of Taicang Huarui Vacuum Furnace Industry Co., Ltd. adopts graphite heating elements and multi-layer insulation structure, ensuring that the temperature uniformity inside the furnace is ≤±3℃, providing a stable environment for the uniform release of stress. Its slow heating and cooling rate design avoids the generation of new stress in titanium alloys due to thermal shock.
Vacuum bright annealing of stainless steel medical devices
Stainless steel medical devices have strict requirements for surface quality and corrosion resistance. Traditional annealing can easily lead to surface oxidation and discoloration, requiring acid washing treatment, which not only pollutes the environment but also affects dimensional accuracy. After a certain medical device enterprise adopted the vacuum bright annealing furnace of Taicang Huarui Vacuum Furnace Industry Co., LTD., it achieved the non-oxidation treatment of stainless steel parts. The 316L stainless steel surgical forceps produced by this enterprise were previously treated with a common annealing furnace, resulting in a blue-black oxide scale on the surface that needed to be removed by acid washing. This led to a decrease in the dimensional accuracy of the forceps jaws and a reduction in the corrosion resistance of the surface after acid washing. After switching to the Huarui vacuum bright annealing furnace, the process parameters are as follows: under a vacuum degree of 1×10⁻¹Pa, heat up to 1050℃, hold for 1 hour, and then introduce argon gas to cool down to 300℃ before removing from the furnace. The surface of the processed surgical forceps is as bright as new, presenting a uniform silver-white color, with a roughness maintained at Ra0.8μm. It can directly enter the assembly process without any surface treatment. Salt spray tests show that its corrosion resistance has been improved from 24 hours without rust to 72 hours without rust, meeting the usage requirements of medical devices. In addition, the non-oxidizing heating in a vacuum environment reduces the intergranular corrosion on the material surface, extending the service life of the surgical forceps by more than three times. The vacuum bright annealing furnace of Taicang Huarui Vacuum Furnace Industry Co., Ltd. adopts precise atmosphere control. By adjusting the argon gas flow rate and cooling rate, it ensures that stainless steel not only eliminates stress but also maintains surface smoothness during the annealing process, providing a guarantee for the high-quality production of medical devices.
Vacuum quenching treatment of bearing steel rollers
Bearing steel rollers require extremely high hardness, wear resistance and dimensional stability. Traditional quenching is prone to problems such as roller deformation and surface decarburization, which affect the rotational accuracy of the bearing. After a certain bearing manufacturing enterprise introduced the vacuum oil quenching furnace of Taicang Huarui Vacuum Furnace Industry Co., LTD., the heat treatment quality of the rollers has been significantly improved. The φ20mm bearing steel rollers produced by this enterprise are made of GCr15 material. Previously, they were quenched in a mesh belt furnace, resulting in a decarburization layer of 0.05mm on both end faces of the rollers, and the roundness error exceeded 0.03mm, causing the vibration value of the bearing to exceed the standard after assembly. The treatment process using Huarui vacuum oil quenching furnace is as follows: Heat to 860℃ under a vacuum degree of 5×10⁻²Pa, hold for 90 minutes, quench in oil at 80℃, and then temper at 180℃ for 2 hours. The treated roller surface has no decarburization, with a hardness reaching HRC62-64, and the hardness distribution is uniform. The hardness difference between the core and the surface is ≤2HRC. The roundness error is controlled within 0.01mm, meeting the assembly requirements of high-precision bearings. The vibration value of the assembled bearing has been raised from the original Z3 group to the Z2 group, and the operating noise has been reduced by more than 5 decibels. Actual installation tests show that the service life of the bearings has been extended from the original 8,000 hours to 12,000 hours. The vacuum oil quenching furnace of Taicang Huarui Vacuum Furnace Industry Co., Ltd. has designed special fixtures for the processing of rollers, ensuring uniform heating of the rollers during heating and cooling. Its precise oil temperature control avoids deformation of the rollers due to uneven cooling, which is a key factor in improving the quality of bearings.
Vacuum isothermal quenching of spring steel
Spring steel requires a relatively high elastic limit and fatigue strength. The traditional quenching and tempering process is prone to cause spring deformation, affecting its elastic performance. After a certain automotive spring manufacturing enterprise adopted the vacuum isothermal quenching furnace of Taicang Huarui Vacuum Furnace Industry Co., LTD., the problem of spring deformation was solved. The 50CrVA automotive suspension springs produced by this enterprise previously adopted the water quenching and oil cooling process. The free height deviation of the springs exceeded 2mm, and there was considerable residual stress. After assembly, plastic deformation was prone to occur. After switching to the Huarui vacuum isothermal quenching furnace, the process was adjusted as follows: Heat to 880℃ under a vacuum degree of 2×10⁻¹Pa, hold for 1 hour, quickly transfer to an isothermal salt bath at 300℃ and maintain for 30 minutes, then air cool. The deviation of the free height of the treated spring is controlled within 0.5mm, the residual stress value is ≤50MPa, and the elastic limit is increased by 15%. Fatigue tests show that the cycle life of the spring has been increased from 500,000 times to 800,000 times, meeting the usage requirements of automotive suspensions. The vacuum isothermal quenching furnace of Taicang Huarui Vacuum Furnace Industry Co., Ltd. adopts a rapid transfer mechanism, ensuring that the time for the spring to move from the heating chamber to the isothermal bath is controlled within 10 seconds, avoiding the temperature drop during the transfer process and guaranteeing the uniform formation of bainite structure. Its precise temperature control provides a guarantee for the stability of the performance of spring steel. The application cases of Huarui vacuum furnaces in metal heat treatment fully demonstrate their advantages in improving product quality, optimizing production processes, and reducing comprehensive costs. Taicang Huarui Vacuum Furnace Industry Co., Ltd. provides customized vacuum heat treatment solutions for various industries by deeply understanding the characteristics and processing requirements of different metal materials. The stability of its equipment and the adaptability of its processes have been widely verified. From die steel to titanium alloys, from medical devices to aviation parts, Huarui vacuum furnaces are promoting the development of metal heat treatment technology towards higher precision, greater environmental friendliness and higher efficiency with their reliable performance, providing strong support for the progress of high-end manufacturing. With the continuous upgrading of industrial technology, the application of Huarui vacuum furnaces in the field of metal heat treatment will become more extensive, solving production problems for more enterprises and creating greater value.
