A porosimeter is a scientific instrument that determines the porous properties of samples. The device can provide data on pore volume, surface area, diameter, and a variety of other topics. Porosimeters are one type of data collection equipment used in materials testing. This testing can also be used for quality assurance, oil and gas exploration, and a variety of other applications in which porosity is a factor.
These devices work by injecting a high-pressure liquid or gas into a sample. Although some devices work with water, mercury is a popular choice of liquid. The best testing material to use is determined by the sample being tested. As the fluid or gas is forced into the material under investigation, porosimeters frequently operate in a vacuum to control air pressure. The amount of pressure required by the porosimeter to overcome surface tension and push the material into the sample provides data on porosity.
Based on the amount of pressure it can generate, the porosimeter’s technical specifications indicate the size of the pores it can measure. For small pores, very high pressure is required, and not all equipment can produce that level of pressure. Larger pores require less pressure because the fluid or gas can flow into them more easily. If the pores are likely to be too small for their equipment, laboratories and materials testing facilities may choose to send some samples to specialty firms.
Porosity is an important characteristic in materials testing. Pore size, volume, and diameter can all indicate how well a material will hold up under pressure. These porosimeter measurements may lead to suggestions for potential uses for the material, and in the case of quality control, it may be necessary to keep materials within a narrow range. To be safe for use in large projects like bridges and high-rise buildings, concrete samples, for example, must follow strict guidelines. Overly porous materials may eventually fail.
Laboratory testing can also be used to gather information about unknown samples. A porosimeter can reveal information about a material’s composition and structure. When combined with other test data, this information could help researchers figure out what’s in a sample and how it behaves under controlled conditions. The more data they gather, the more precisely they can pinpoint the material’s nature. Whether a material is tested in an experiment or on behalf of a client who wants more information about it, a technician can write up the results for reference and review.