Analysis of Functions and Application Fields of Porous Sintered Metal Powder

Porous sintered metal powder, as an outstanding innovation in materials engineering, perfectly combines the excellent properties of metals with the unique advantages of controllable porous structures. This material is prepared through powder metallurgy technology, with the core of forming and high-temperature sintering metal or alloy powders to form a network structure with interconnected or closed pores. With its precisely controllable pore characteristics (porosity generally ranging from 30% to 60%, pore size range from 1-100 microns) and excellent physical and chemical properties, this type of material has demonstrated irreplaceable value in many industrial fields. The following content will delve into its multifunctional features and wide range of application scenarios.

Why has porous sintered metal powder become a key material in the industrial field?

Porous sintered metal powder, often referred to as porous sintered material, is made from metal or alloy powders (such as bronze, stainless steel, iron, nickel, titanium and their alloys) through forming and sintering processes. Its internal pores are crisscrossed and interconnected, which gives it the characteristics of both functional and structural materials.

The fundamental characteristics of materials are the basis for their widespread application. It not only has controllable pore size and porosity, but also excellent permeability, thermal conductivity, and electrical conductivity, and is resistant to high and low temperatures, thermal shock, and medium corrosion. Compared with traditional filtering materials such as paper, ceramics, or wire mesh, sintered metal porous materials perform better in strength, service life, and regeneration performance (the filtration performance can be restored to over 90% after regeneration), making them suitable for more demanding working environments.

The diversity of preparation processes ensures the designability of material properties. According to the shape and performance requirements of the product, various traditional methods such as compression molding, isostatic pressing, powder rolling, and loose fitting sintering can be used. In recent years, emerging technologies such as Metal Injection Molding (MIM), 3D printing technology (such as Selective Laser Sintering (SLS)), and centrifugal deposition technology have further enhanced the ability to prepare complex shapes and high-precision porous structures. The particle size, shape (spherical or irregular), and distribution of raw material powder are key factors determining the final pore structure.

How can porous sintered metal powders solve industrial problems through their multifunctional properties?

1. Precision separation and filtration function

One of the core functions of porous sintered metal powder is filtration and separation. The interconnected pore structure inside allows fluid (gas or liquid) to pass through while effectively intercepting solid particles larger than a specific size.

-Widely applicable: From fuel oil and air purification in airplanes and cars, to filtration of various corrosive media in the chemical industry, and even removal of radioactive particles in the atomic energy industry, its presence can be seen. It is worth mentioning that porous materials prepared from high melting point metals such as titanium and tungsten or ceramics can also be used for high-temperature gas purification and even filtration of molten metals. -Excellent Performance: As a filter, it has outstanding advantages such as high filtration accuracy, good separation effect, high filtration speed, high strength, high pressure resistance, corrosion resistance, and good regeneration performance. When the pores are small to a specific scale, they can also be used as molecular sieves for gas separation.

2. Energy management and thermal control functions

Porous sintered metal powders exhibit excellent performance in thermal management and energy control .

-Heat exchange application: Its excellent thermal conductivity and large specific surface area make it an ideal material for heat exchangers, heaters, and radiators, achieving high heat exchange efficiency. For example, powder metallurgy porous steel can be used to manufacture exhaust manifolds for automotive engines, adapting to working environments with a wide temperature range. -Energy buffering and absorption: Thanks to its porous structure, this type of material can effectively absorb kinetic energy and is commonly used in the manufacture of buffers and shock absorbers. In the aerospace industry, landing gear is used for spacecraft, and in the automotive industry, it is used for impact protection and other impact zones. It can consume energy and improve safety through controllable deformation. Filling porous materials (such as porous aluminum) into hollow components can improve their deformation behavior and achieve a balance between lightweight and high energy absorption capacity.

3. Sound wave attenuation and pressure regulation function

Porous sintered metal powders also play an important role in the fields of noise control and pressure management.

-Sound wave attenuation: When sound waves propagate through the pores of materials, they generate significant internal friction and reflection refraction, converting sound energy into thermal energy and achieving excellent sound absorption and noise reduction effects. This characteristic makes it widely used in building acoustics (such as gym ceilings), automated office equipment, radio recording studios, and even submarine partitions to counter sonar tracking. -Flow field and pressure control: Porous structures can be used for precise control of fluid flow (gas or liquid). For example, it can be used as a breathable element for fluid distribution plates, rocket nose cone yaw indicator housings, or as a gas or liquid meter or delay device to achieve uniform distribution and stable control of fluids. Its flame retardant and explosion-proof functions (such as gas welding flame explosion-proof devices) are also based on its ability to suppress pressure and flame propagation.

4. Electrochemical and catalytic reaction functions

The huge specific surface area and good conductivity make porous sintered metal powders shine in the fields of electrochemistry and catalysis.

• Electrode Material: Porous nickel is widely used as an electrode material in various batteries, fuel cells, and air batteries. Porous copper and porous lead can also be used as active material supports for electrolytic cathodes and lead-acid batteries, respectively, helping to reduce electrode weight and improve energy density.
• Catalyst carrier: Its large specific surface area and support strength make it an ideal choice for efficient catalysts or catalyst carriers. In multiphase catalytic reactions, reactant molecules are adsorbed and activated on a large surface, which can significantly reduce the activation energy of the reaction and accelerate the reaction rate. This is crucial for applications in the fields of chemical engineering, environmental protection, and energy, such as high-temperature gas purification.

The following table summarizes porous sintered metal powders of different materials and their typical application environments:

How can porous sintered metal powders demonstrate their potential in high-end technology and green energy?

With the development of technology, the application of porous sintered metal powders has entered many cutting-edge fields.

In the field of biomedicine, artificial bones, joints, and dental implants prepared using porous titanium or TiNi intermetallic compounds have become ideal biomaterials due to their excellent biocompatibility and bone integration ability. In the field of green energy and environmental protection, porous sintered metals are the core materials for key components of fuel cells, such as porous electrodes, and are also used in environmental protection technologies such as high-temperature flue gas purification and water treatment.

In the fields of aerospace and high-end manufacturing, its application goes far beyond filtration itself. For example, sweating materials made using the principle of surface sweating cooling can be used for high-temperature components such as rocket engine nozzles, effectively reducing surface temperature. Lightweight structural components made of porous materials, such as aircraft skin core materials, significantly reduce the weight of aircraft while ensuring performance. In addition, its electromagnetic shielding function is becoming increasingly important in preventing interference in electronic devices.

What is the future development direction of porous sintered metal powders?

The future of porous sintered metal powders is full of opportunities. On the one hand, with the continuous innovation of preparation technology, such as additive manufacturing (3D printing), mechanical alloying and other new processes, it has become possible to prepare porous materials with more precise pore structures, more complex compositions and better performance. On the other hand, the continuous improvement of material performance requirements is driving the development of new porous material systems, such as intermetallic compound porous materials (TiAl, Fe3Al, etc.) and high-performance alloy porous materials, to meet the application needs of extreme environments (high temperature, strong corrosion).

At the same time, material design and application are developing towards multifunctionality and intelligence. Combining the permeability and ultra-high specific surface area of porous materials with other physical and chemical functions to develop intelligent materials with multiple functions such as separation, catalysis, and sensing will be an important trend in the future. All of this indicates that porous sintered metal powder, as a key basic functional material, will play an increasingly important role in achieving efficient, clean, and sustainable industrial processes.