Today, with the rapid development of the electronics industry, aluminum nitride ceramics have become the first choice for large-scale integrated circuit cooling substrates and packaging materials because of their excellent thermal conductivity, excellent mechanical properties, corrosion resistance and good electrical properties. Especially in the pursuit of miniaturization and high performance integrated circuit chips, the lightweight and ultra-smooth surface of aluminum nitride substrates become the key to improve the overall performance. However, the high hardness, high brittleness and low fracture toughness of aluminum nitride ceramics have brought great challenges to its ultra-precision machining. How to achieve surface roughness as low as nanometer level without damaging the material itself has become a technical problem to be solved urgently in scientific research and industry. This paper focuses on the magnetorheological polishing process of aluminum nitride ceramics, and discusses how to effectively deal with these challenges and achieve high quality flat machined surfaces.
Magnetorheological polishing technology, as an innovative ultra-precision machining method, cleverly combines magnetic field control and fluid mechanics principles to achieve non-contact or low contact stress polishing of material surfaces. By adjusting the intensity and distribution of the magnetic field, the arrangement and motion of the magnetic particles in the magnetorheological fluid are controlled to form a dynamic and controllable polishing film on the surface of the workpiece. This polishing film can remove tiny bumps on the surface of the material with extremely high accuracy and efficiency under very small contact pressure, achieving a surface roughness of nanometer level.
For aluminum nitride ceramics, magnetorheological polishing technology has shown significant advantages. First of all, since there is almost no direct contact in the polishing process, the mechanical and thermal stress that may be caused by traditional polishing methods is avoided, and the surface defects and sub-surface damage generated during the processing are significantly reduced. Secondly, magnetorheological polishing has a high degree of controllability. By precisely adjusting process parameters, such as magnetic field strength, polishing fluid flow rate and specimen speed, it can achieve accurate machining of aluminum nitride ceramic substrates of different shapes and sizes to meet diverse processing needs.
In addition, magnetorheological polishing technology also has a high material removal rate and processing efficiency. The results show that under suitable process conditions, magnetorheological polishing process of aluminum nitride ceramics can achieve surface accuracy of RMS value less than 2 nm, while maintaining high processing speed, which is of great significance for improving production efficiency and reducing production cost.
In summary, the magnetorheological polishing process of aluminum nitride ceramics, with its unique non-contact or low contact stress polishing mechanism, effectively overcomes the processing problems caused by high hardness, high brittleness and low fracture toughness of aluminum nitride ceramics, and provides a new solution for obtaining high-quality flat machined surfaces. With the continuous maturity and optimization of technology, magnetorheological polishing technology is expected to show its great potential in more fields such as electronic packaging, optical components, precision machinery, and promote the development of related industries in the direction of higher precision and higher efficiency. In the future, we look forward to further expanding the application scope of magnetorheological polishing technology through continuous research and innovation, and contributing more to scientific and technological progress and social development.
