Three elements factors temperature vacuum sintering furnace outward transfer

Three elements factors temperature vacuum sintering furnace outward transfer

According to the distribution of temperature field equations, the distribution of heat throughout the vacuum smelting furnace temperature field, depending on several aspects of constraint. That average thermal conductivity of the material, the average density of the material P and the average ratio of melt c. . Factors in Vacuum Furnace outward transfer, including the following three points:
① strength furnace heat yuan roar, in this design, mainly in the form of heat. Internal heat source, the temperature passes from the inside to the outside. Its strength directly affects the size of the furnace temperature distribution. As it can be seen from (5), the higher the heat source when the roar, the higher the temperature of a certain point, while a certain temperature difference (△ T) distribution area (r) increases. Therefore, in the actual production process, by controlling the furnace core surface load ie furnace core power distribution control furnace temperature.
② reaction furnace feed distance from the core (△ r), when the furnace core constant power, constant source of strength that is within, the farther away from the reaction furnace core material, the lower the temperature, the reaction may not reach the desired temperature. Furnace core from the closer, the higher the temperature, the more beneficial to the reaction.
③ charge thermal performance, the better the thermal performance of the charge, the faster the loss of internal heat outside, it is easy to heat loss outside of the reaction material, resulting in a certain point temperature decreases. However, if the material of the reaction thermal performance is not good, the heat conducive to aggregation, so that heat transfer outwardly extended time to facilitate the reaction of the heat absorbing material and the reaction carried out to raise the temperature of some points. Should be in high vacuum (4 ~ 13Pa) carried out a reaction temperature of about 1200 deg.] C, the core temperature quickly reaches the desired value, and therefore the reaction time depends on the thickness of the reaction material, i.e., the reaction furnace is fed die periphery from the furnace insulation layer. It can be designed to control the size of the furnace operation time.

Safety characteristics of vacuum sintering furnace

Safety characteristics of vacuum sintering furnace

The vacuum technology of heat treatment of vacuum sintering furnace and heat treatment combining two professional integrated technology, refers to the whole and part of heat treatment process in a vacuum. Our country could be divided into low, medium and high vacuum and high vacuum. At present most of the vacuum heat treatment furnace work vacuum degree in 1.33 ~ 1.33 x 10 ˉ after Pa.
Vacuum heat treatment can achieve almost all heat treatment process, such as quenching, annealing, tempering, carburizing, nitriding, during the quenching process can realize gas quenching, quenching oil, water nitrate quenching, quenching, etc., can also be vacuum brazing, sintering and surface treatment, etc. Vacuum heat treatment furnace thermal efficiency is high, which can realize the rapid heating and cooling, which can realize no oxidation and decarburization, carburizing, can remove phosphorus crumbs on the surface of the workpiece, and has the effect such as degreasing degassing, so as to achieve the surface brightness purification effect. Generally speaking, the processed workpiece in the heating furnace is slow, and internal temperature difference is small, the thermal stress is small, so little deformation. Product qualified rate is high. Can reduce costs, have degassing effect, so as to improve the mechanical properties of the work and life. Good working environment, safety operation, no pollution and no pollution. Be processed workpiece no hydrogen embrittlement risk, to prevent surface of the titanium and refractory metal shell hydrogen embrittlement, stability and repeatability of vacuum heat treatment process. A series of advantages, the development of vacuum heat treatment equipment and process was more and more attention and applied more and more.

The role of low pressure sintering

The role of low pressure sintering

Low pressure sintering furnace is compatible with the dewaxing, vacuum sintering, low pressure sintering, low pressure processing, multiple functions such as sintering atmosphere. Mainly used for: pressure before products of low pressure sintering; The low pressure processing of sintered products; The carbon sintering pressure products.
Low pressure sintering's main function is to reduce the microscopic pore in cemented carbide. The porosity of the sintered body in the vacuum sintering stage has been eliminated. Microscopic pore pressure stage mainly eliminated.
Low porosity is an important symbol of high quality hard alloy, try to reduce the porosity in the cemented carbide in the production, is one of the main pursuit of carbide workers.
Carbide densification and capillary force, the wettability of liquid phase for solid phase and the surface tension of the liquid has a close relation with the associated, as in the process of sintering temperature, when a liquid phase, due to the capillary pressure, the liquid phase to the surface of WC mobile, because the liquid has good wettability to WC phase, liquid phase was attached to the surface of WC, because the surface tension of the liquid phase, driven by liquid package WC mobile, strong contraction occurs at this point. In WC mobile liquid package, in the process of contraction, exists in the gas is out of briquetting, due to the flow of the liquid phase, a part of the porosity of the sintered body is liquid closed, with the augmentation of the contract, enclosed within the pore pressure, when the surface tension is equal to or less than the pressure in the pore, closed pore preserved in the alloy, microscopic pore space.

Vacuum sintering furnace is what?

Vacuum sintering furnace is what?

Vacuum sintering furnace is heated objects to make use of induction heating protective sintering furnace, can be divided into the power frequency, medium frequency, high-frequency, such as type, can be ascribed to a subclass of vacuum sintering furnace.
    Vacuum induction furnace is under vacuum or protective atmosphere conditions, using the principle of intermediate frequency induction heating make hard alloy tool bit and all kinds of metal powder compacting sintering of complete sets of equipment, is for hard alloy, metal dysprosium, designed in the industrial production of ceramic materials.
   Main principle and use vacuum sintering furnace is after vacuum filling hydrogen protection condition, by using the principle of intermediate frequency induction heating, the high temperature of tungsten crucible in the winding, by heat conduction to work on, suitable for scientific research, military units for hard metal such as tungsten, molybdenum and its alloy powder sintering molding.
    The main structure and structure form is vertical, the discharging more ways. Its main composition is: the furnace body, vacuum system, water cooling system, pneumatic system, hydraulic system and front-rear institutions, base, workbench, induction heating device (tungsten heater and advanced thermal insulation material), into the electric device, medium frequency power supply and electric control system, etc.
    Main function after vacuum filling the hydrogen gas protection and control atmosphere in furnace pressure and sintering condition. Available optical fiber infrared radiation thermometer and armoured thermocouple temperature measurement (0 ~ 2500 ℃), and through the intelligent temperature control after comparing with the setup program, select the execution state feedback to intermediate frequency power supply, automatic control temperature and heat preservation program.

The maintenance and maintenance of vacuum sintering furnace

The maintenance and maintenance of vacuum sintering furnace

1, according to the PLC program of low vacuum: all the vacuum valve closed, start the mechanical pump, after waiting for its running normally (about 1 to 2 min), open to the furnace of low vacuum valve disc valve, in advance of furnace smoke low vacuum;
2, according to the PLC program, high vacuum, open the valve disc, the diffusion pump suction, after 15 Pa under vacuum, the system automatically open to preheat diffusion pump, diffusion pump in about after 45 min started its function, can closed on disc valve, at the same time open the main stop valve for vacuum degree of 1.33 x 10 Pa, the samples can only open the heating button to heat.
Vacuum sintering furnace maintenance guide equipment operators within the scope of responsibility of equipment point check parts, with the right inspection methods and tools based on the tally equipment daily maintenance cycle; The operator work should be carried out according to the daily maintenance manual. According to the technical requirements after the installation of complete equipment, perfect and has a good grounding, debugging and acceptance in accordance with the following items.

The role of the low-pressure sintering furnace

                          The role of the low-pressure sintering furnace

Low pressure sintering furnace is compatible with the dewaxing, vacuum sintering, low pressure sintering, low pressure processing, multiple functions such as sintering atmosphere. Mainly used for: pressure before products of low pressure sintering; The low pressure processing of sintered products; The carbon sintering pressure products.
Low pressure sintering's main function is to reduce the microscopic pore in cemented carbide. The porosity of the sintered body in the vacuum sintering stage has been eliminated. Microscopic pore pressure stage mainly eliminated.
Low porosity is an important symbol of high quality hard alloy, try to reduce the porosity in the cemented carbide in the production, is one of the main pursuit of carbide workers.
Carbide densification and capillary force, the wettability of liquid phase for solid phase and the surface tension of the liquid has a close relation with the associated, as in the process of sintering temperature, when a liquid phase, due to the capillary pressure, the liquid phase to the surface of WC mobile, because the liquid has good wettability to WC phase, liquid phase was attached to the surface of WC, because the surface tension of the liquid phase, driven by liquid package WC mobile, strong contraction occurs at this point. In WC mobile liquid package, in the process of contraction, exists in the gas is out of briquetting, due to the flow of the liquid phase, a part of the porosity of the sintered body is liquid closed, with the augmentation of the contract, enclosed within the pore pressure, when the surface tension is equal to or less than the pressure in the pore, closed pore preserved in the alloy, microscopic pore space.

The main performance parameters of the powder sintering furnace

The main performance parameters of the powder sintering furnace

Power supply: 380 v, 50 hz
Working temperature: room temperature + 10-250 ℃, at any temperature can be set
The shell material: hot rolled steel plate, the surface coating of paint
The tank system material: high temperature resistant stainless steel plate, silicon carbide combined with silicon nitride muff
Heater: stainless steel pipe spiral wire electric heater, silicon carbon rod
Heater location: two layers of heating up and down
Insulation: 1260 aluminum silicate cotton carbon
Temperature control: PID temperature controller, LED digital display, buttons, automatic constant temperature
Temperature sensing element: S type high temperature thermocouple
Security protection, short circuit protection, overload protection, motor thermal overload, open phase protection, nitrogen in the hearth, decomposition of ammonia gas, such as protection, adopt import stainless steel mesh belt, transmission system adopts frequency control of motor speed.