Can the experimental box type muffle furnace be evacuated?

Whether the experimental box type muffle furnace can be evacuated depends on the specific model:

Traditional box type muffle furnace: usually does not have vacuum pumping function. The furnace body is composed of refractory materials such as ceramic fibers and high alumina bricks, as well as a metal shell, which has poor sealing and cannot withstand high vacuum environments (such as excessive internal and external pressure differences that may cause deformation or rupture of the furnace body). This type of equipment is mainly used for routine experiments under air or inert gas protection (such as ashing, burning, ceramic sintering, etc.), and forcibly vacuuming will damage the equipment.
Vacuum box type muffle furnace: designed specifically for vacuum environments, supporting vacuum extraction operations. Its core features include:
Sealing structure: The furnace body is welded with metal (such as stainless steel) and equipped with vacuum flanges and sealing rings to ensure airtightness.
Vacuum system: Integrated mechanical pump (pre pumping to low vacuum) and molecular pump (further pumping to high vacuum, such as below 10 ⁻ Pa), to meet the experimental needs sensitive to atmosphere (such as rare metal and semiconductor material processing).
Heating method: Use graphite heater or molybdenum heating wire to meet the high temperature requirements in a vacuum environment (up to 1800 ℃).
Safety protection: It has functions such as over temperature protection, leakage protection, and overpressure alarm. The vacuum system is equipped with anti backflow oil device to ensure operational safety.

Typical application scenarios of vacuum box type muffle furnace:
Metal material processing: vacuum annealing (such as titanium alloy annealing to avoid the formation of oxide layer), quenching (to reduce cracks caused by thermal stress).
Ceramic material sintering: oxygen free sintering (such as silicon carbide and aluminum nitride sintering to prevent oxidation and performance degradation).
Electronic industry: semiconductor component packaging heat treatment, photovoltaic material preparation (such as silicon ingot annealing).
Nanomaterial synthesis: preparation of carbon nanotubes and graphene (vacuum environment to avoid impurity contamination).
Example of operation process (taking vacuum annealing as an example):
Preprocessing: Check the sealing of the furnace body and confirm that the vacuum pump, molecular pump, and cooling water system are functioning properly.
Vacuum pumping: Close the furnace door and vacuum valve, start the mechanical pump to pre pump to below 7.6 Pa, and then start the molecular pump to pump to the target vacuum degree (such as 10 ⁻ Pa).
Heating: Turn on the cooling water, start the heating program when the vacuum degree reaches the standard, and heat up to the target temperature (such as 800 ℃) according to the set curve.
Insulation and cooling: Keep at the target temperature for 2 hours, then cool down with the furnace to below 100 ℃.
Sampling: Turn off the molecular pump and cooling water, release air, and open the furnace door to take out the sample.

Purchase suggestion:
Clear requirement: If the experiment requires a vacuum environment (such as metal purification, semiconductor material processing), a vacuum box type muffle furnace should be selected; If only conventional heating or inert gas protection is needed, traditional box type muffle furnaces can meet the requirements.
Key parameters: Pay attention to the highest temperature (such as 1600 ℃ or 1800 ℃), vacuum degree (such as 10 ⁻ ³ Pa), furnace size (such as 300 × 200 × 200 mm), temperature control accuracy (such as ± 1 ℃), etc.