1.Description:

This instrument is suitable for determining the maximum value of the capillary pores in porous ceramics according to GB/T1967-1996 "Test Method for Pore Diameter of Porous Ceramics". The instrument is mainly composed of an air supply cylinder, an electrical control box, and a sample fixture. It uses a precise low-range digital pressure measurement system to accurately measure the test pressure value. The test gas is compressed air or nitrogen; the sample fixture is suitable for samples with a cylindrical cross-section, and the fixture ensures that the Xiangtan Xiangke DZK porous ceramic pore diameter tester
This instrument is suitable for determining the maximum value of the capillary pores in porous ceramics according to GB/T1967-1996 "Test Method for Pore Diameter of Porous Ceramics". The instrument is mainly composed of an air supply cylinder, an electrical control box, and a sample fixture. It uses a precise low-range digital pressure measurement system to accurately measure the test pressure value. The test gas is compressed air or nitrogen; the sample fixture is suitable for samples with a cylindrical cross-section, and the fixture ensures that during the test, the gas can only pass through the capillary pores of the sample and will not leak from the edge of the sample.
Working Principle:
This method employs the gas bubble pressure technique, utilizing the principle of capillary action to measure the pore size of the membrane. The surface tension of the wetting agent affects the size of the measured pore. According to the principle of capillary action, when a capillary tube with a radius of r is wetted by a liquid A with a surface tension of σ, and when the relative pressure P2 of the capillary liquid reaches a static equilibrium with the gas phase pressure P1 (liquid B is the gas phase), the relationship between P2 and P1 can be described by the Laplace equation:
ΔP = P2 - P1 = 2σcosθ/r. Here, θ is the contact angle (the cylindrical contact angle is 0).
When the pressure difference between the two ends of the pore is greater than 2σcosθ/r, the liquid in the capillary tube will be removed. The gas bubble pressure method is based on this principle to measure the pore size of porous materials. During the actual measurement process, the liquid with known surface tension is fully (saturated) wetting the pores of the porous ceramic material (vacuuming or boiling), the pressure at one end of the porous material is fixed, and a pressure difference is generated at the other end using air or nitrogen. When the pressure difference reaches a certain value, the maximum pore diameter of the porous material is first opened, and the pore size is calculated according to the above formula.

2.Technical Parameter