Vacuum Sintering Furnace Purchasing Guide
Vacuum induction sintering furnace is a complete set of equipment which uses the principle of medium frequency induction heating to realize sintering under vacuum or protective atmosphere. It is widely used in sintering of active and insoluble metals, cemented carbide, magnetic materials and stainless steel. For the selection of vacuum sintering furnace, we should pay attention to at least 12 selection criteria to ensure the purchase of high quality vacuum sintering furnace products.
1. Uniformity of Temperature Zone in Furnace
It must be measured at different temperature points, such as 300, 600, 900, 1400 and so on. It is not possible to measure only one high temperature zone, because the heating electrodes of the furnace are different in different temperature states. Thermometers can be used below 1000 degrees, and temperature measuring rings can be used above 1000 degrees.
2. Fever material and accessories
If graphite is used, it must be high-purity graphite, preferably imported, insulating material must be good, and the wiring structure is not easy to lead to short circuit, or wait for repair.
It is necessary to consider the ultimate vacuum degree and leakage rate, which is related to the good sealing of the furnace, and the vacuum furnace has a very close relationship with the temperature rise. Ignoring the ideal conditions of vacuum chamber leakage and material outgassing, the vacuum chamber pressure has a great relationship with the temperature rise rate. For a certain pumping rate, if the temperature rise rate is determined, the law of pressure change will tend to be the same. If the heating rate is too fast, the pressure will increase beyond a certain critical value; if the temperature is lowered, the pressure will inevitably decrease.
4. Vacuum time
The time of pumping the limit vacuum is related to the quality of mechanical pumps and Roots pumps. Whether the time to reach vacuum is too long is also a question to consider when purchasing equipment.
5. Heating rate
The speed of heating up is related to whether the choice of thermocouple is reasonable or not. When buying, we should first determine the temperature we need, and then compare and choose. The speed of heating also reflects the quality of thermocouples. Thermocouples must be dual-core, or one of them will burn out in the process of use, which will cause trouble.
6. Cooling speed
Cooling speed (production efficiency) from the highest temperature to room temperature, with or without quick cooling device. After the workpiece is processed, the low vacuum valve is closed and the mechanical pump is stopped. Only after the diffusion pump is completely cooled, the cooling water supply is cut off. Otherwise, the equipment will be greatly affected. Whether there is a fast cooling device or not is also a problem that users need to consider when choosing and purchasing.
7. Specification and Model of Vacuum Gauge
Some vacuum gauges are not resistant to pollution and will fail. If the vacuum requirement is not high, we can ask the manufacturer to equip an additional Pirani vacuum gauge, which is very practical.
8. glue collector
Generally, products are mixed with glue or paraffin, so you should pay attention to the fact that the cleaning port of the wax collecting device must be opened conveniently. At the same time, if paraffin and other solid moulding agents are used at room temperature, the wax collecting device must be able to heat.
9. Satisfaction of Special Gases
Whether process gases can be passed through involves the need for use. If sintered products sometimes need some gases, then this must be done.
10. Is it complete after-sale
Some manufacturers offer one-time product sales, but do not provide a separate purchase of vulnerable parts, here we need to take this factor into account, otherwise the stove is not damaged but because of a vulnerable parts delay can not use embarrassment!
The above guide for selecting and purchasing vacuum sintering furnaces, for users, as long as referring to these standards and combined with their own needs, I believe that the appropriate equipment can be selected.