A solid containing a certain number of pores is called a porous material. The boundaries or surfaces of the pores are formed by pillars or flat plates.

According to the size of the pores, porous materials can be divided into microporous (pore diameter less than 2 nm) materials, mesoporous (pore diameter 2-50 nm) materials and macroporous (pore diameter greater than 50 nm) materials.
Compared with continuous media materials, porous materials generally have the advantages of low relative density, high specific strength, high specific surface area, lightweight, sound insulation, heat insulation, and good permeability. Specifically, porous materials generally have the following six characteristics:
Mechanical behavior
The application of porous materials can improve mechanical properties such as strength and stiffness, while reducing density. This application has certain advantages in the aerospace and aviation industries. According to calculations, if the aircraft is replaced with porous materials, the weight of the aircraft will be reduced under the same performance conditions. to half of its original size. Another change in the mechanical properties of porous materials is the improvement of impact toughness. Application in the automotive industry can effectively reduce the damage caused to passengers in traffic accidents.
propagation performance
When waves propagate to the interface of two media, reflection and refraction occur. Due to the existence of porosities, the possibility of reflection and refraction increases, and the possibility of diffraction also increases. Therefore, porous materials can block waves. Taking advantage of this property, porous materials can be used as sound insulation materials, vibration damping materials, and explosion impact-resistant materials.
Optoelectronic properties
Porous materials have unique optical properties. Microporous porous silicon materials can emit visible light under laser irradiation and will become an ideal material for manufacturing new optoelectronic components. The special photoelectric properties of porous materials can also be used to create porous electrodes for fuel cells, which are considered the most promising energy devices for the next generation of automobiles.
Permeability
Because people have been able to produce porous materials with regular hole shapes and regular arrangements, the size and direction of the holes can be controlled. This property can be used to make molecular sieves, such as high-efficiency gas separation membranes, reusable special filtration devices, etc.
adsorption
Since each gas or liquid molecule has a different diameter and a different degree of freedom of movement, porous materials with different pore sizes have different adsorption capabilities for different gases or liquids. This property can be exploited to create efficient gas or liquid separation membranes for air or water purification, which can even be reused.
Chemical properties
As the density of porous materials decreases, the activity of general materials will increase. Artificial enzymes based on porous materials with molecular recognition functions can greatly increase the speed of catalytic reactions.
Although the mechanical properties and corrosion resistance of sintered porous materials are inferior to those of dense metals due to the presence of pores, some properties such as heat exchange capacity, electrochemical activity, catalysis, etc. are much better than dense metals due to the increased specific surface area. Porous materials also have a series of functions that dense metals do not have. For example, the pores can penetrate gas and liquid media, absorb energy, or act as a buffer. Sintered porous materials have special properties due to different uses. For example, filter materials require filtration accuracy, permeability, and regeneration; some porous materials require heat exchange efficiency, electrochemical activity, acoustic resistance, electron emission capability, etc.
The main parameters characterizing the porous structure are porosity, average pore diameter, maximum pore diameter, pore size distribution, pore shape, and specific surface. In addition to the material, the porous structure parameters of the material have a decisive influence on the mechanical properties and various performance properties of the material.


The porous materials we provide mainly include porous ceramics, porous titanium, porous stainless steel, and porous tungsten.