I. Introduction
PCD (polycrystalline diamond) composite sheets for tools, as a superhard material, play an extremely important role in the field of modern mechanical processing. It combines the high hardness and high wear resistance of diamond with the high strength and high toughness of cemented carbide, and is widely used in the precision processing of non-ferrous metals, non-metallic materials and high-hardness alloy materials.
II. Structure and Performance Characteristics of Composite Sheets for PCD Tools
Structure
Composite sheets for PCD tools are usually composed of a diamond layer and a cemented carbide matrix. The diamond layer is sintered by numerous fine diamond micropowders under high temperature and high pressure conditions, and its thickness is generally between 0.5 and 2mm. The cemented carbide matrix provides good support for the diamond layer, ensuring the overall strength and stability of the composite sheet during use.
Performance Characteristics
High hardness: Diamond has extremely high hardness, with a Mohs hardness of up to 10, which enables PCD tools to easily cut materials with higher hardness, and maintain the sharpness of the tool edge during long-term cutting, reducing the frequency of tool replacement and improving processing efficiency.
High wear resistance: Its wear resistance is much higher than that of traditional tool materials. During the processing, the tool wear is extremely small, which can ensure the accuracy of the processing size and the stability of the surface quality. It is particularly suitable for precision processing in large-scale production.
High thermal conductivity: Good thermal conductivity helps to quickly dissipate heat during the cutting process, reduce the tool temperature, reduce tool wear and workpiece thermal deformation caused by high temperature, thereby improving processing accuracy and tool life.
Low friction coefficient: The low friction coefficient between the processed material is conducive to reducing cutting force and energy consumption during processing. It also reduces the roughness of the processed surface and improves the surface quality of the workpiece.
III. Preparation process
Raw material selection
The quality of diamond powder has a great influence on the performance of PCD tool composite sheets. Generally, diamond powder with uniform particle size and high purity is selected, and its particle size range is usually between 5-50μm. The cemented carbide matrix needs to have high strength, high toughness and good bonding properties. Commonly used cemented carbide matrix materials include WC-Co, etc.
High temperature and high pressure synthesis process
The selected diamond powder and cemented carbide matrix are placed in a special mold and synthesized under high temperature and high pressure conditions. The synthesis temperature is generally 1300-1500℃, and the pressure is about 5-6GPa. Under high temperature and high pressure environment, the diamond powders combine with each other to form a continuous diamond layer and are firmly bonded to the cemented carbide matrix.
Post-processing process
The synthesized PCD composite sheet needs to be cut, ground, polished and other post-processing processes to obtain the required dimensional accuracy and surface quality. Cutting usually uses methods such as laser cutting or electric spark cutting, and grinding and polishing can use tools such as diamond grinding wheels to gradually reduce the surface roughness of the composite sheet and improve its flatness.
IV. Application field
Automobile manufacturing industry
Widely used in the processing of aluminum alloy parts such as automobile engine cylinder blocks and cylinder heads. PCD tools can efficiently cut aluminum alloy materials, ensure processing accuracy and surface quality, and improve the production efficiency and performance of automobile engines.
Aerospace field
Used for processing difficult-to-process materials such as titanium alloys and carbon fiber composites in aerospace parts. Its high hardness and high wear resistance can meet the high-precision processing requirements of these materials and ensure the quality and reliability of aerospace parts.
Electronic information industry
In the processing of printed circuit boards (PCBs), PCD tools can be used for drilling, milling and other processing procedures. Due to its good processing performance, it can improve the processing quality and production efficiency of PCBs and meet the needs of the rapid development of the electronic information industry.
V. Market status and development trends
Market status
At present, the global PCD tool composite sheet market is mainly dominated by a few internationally renowned companies, such as Element Six in the United States and Sumitomo Electric in Japan. These companies have obvious advantages in technology research and development, product quality and market share. There are also some domestic companies engaged in the production of PCD tool composite sheets, but there is still a certain gap between the technical level and product quality and the international advanced level. However, with the rapid development of the domestic manufacturing industry, the demand for PCD tool composite sheets is increasing, and domestic companies are also continuously increasing their R&D investment and striving to improve their own technical level and market competitiveness.
Development Trend
High performance: In the future, PCD tool composite sheets will develop towards higher hardness, better wear resistance and higher toughness to meet the ever-increasing mechanical processing requirements, such as the cutting requirements for harder and more difficult-to-process materials.
Refined: With the development of precision machining technology, the dimensional accuracy and surface quality requirements of PCD tool composite sheets will become higher and higher, and its preparation process will be more refined to ensure that products that meet precision machining requirements can be produced.
Multifunctional: In addition to the existing cutting performance, PCD tool composite sheets may be given more functions, such as self-lubricating function, anti-corrosion function, etc., to further expand its application areas.
VI. Conclusion
PCD tool composite sheets, as a high-performance superhard material, play an irreplaceable role in the field of modern mechanical processing. Although the current market is mainly dominated by internationally renowned companies, domestic companies are also developing and progressing. With the continuous innovation of technology and changes in market demand, PCD tool composite sheets will develop in the direction of high performance, refinement and multifunctionality, and their application areas will continue to expand, providing stronger support for the development of the global manufacturing industry.
