How to improve the wear resistance and impact resistance of cemented carbide cutter heads?
Publish Time: 2025-03-24
As the core cutting element in modern industrial processing, the wear resistance and impact resistance of cemented carbide cutter heads directly determine the processing efficiency and tool life. In the fields of mining, metal processing, building materials production, etc., cemented carbide cutter heads are subjected to severe friction, impact and heat load. How to improve these two key performances has become an important topic in materials science and engineering technology.Material ratio optimization is the basis for improving the performance of cemented carbide cutter heads. Traditional WC-Cocemented carbide balances wear resistance and toughness by adjusting the size of tungsten carbide particles and the ratio of cobalt content. Modern research further introduces multi-component composite carbides, such as adding hard phases such as TiC and TaC, to form a more complex microstructure. Fine-grained cemented carbide (grain size <0.5μm) exhibits excellent comprehensive performance, with a hardness of more than HRA92 and a fracture toughness increase of 30%. By precisely controlling the sintering process, a uniformly distributed cobalt phase network can be obtained, which not only ensures the support of the hard phase but also provides sufficient metal toughness phase.The application of surface engineering technology has brought revolutionary improvements to cemented carbide tool heads. Physical vapor deposition (PVD) and chemical vapor deposition (CVD) technologies can form ultra-hard coatings several microns thick on the surface of the tool head. Nano-multilayer coatings such as TiAlN and AlCrN not only have a hardness of more than HV3000, but also have excellent thermal stability and oxidation resistance. The newly developed diamond-like carbon (DLC) coating reduces the friction coefficient to below 0.1, significantly reducing the cutting temperature. These coatings are strongly bonded to the substrate through a gradient transition layer to avoid peeling failure. Laser surface alloying technology can change the surface microstructure, form a fine-grained strengthening layer, and improve the surface wear resistance without changing the performance of the substrate.Microstructure design innovation is the key to improving impact resistance. By introducing special grain boundary engineering, such as constructing a directional arrangement structure of WC grains, cracks can be guided to expand along a specific path, consuming more fracture energy. The layered structure design inspired by bionics imitates the organic-inorganic hybrid characteristics of shells, allowing the material to absorb energy through microcrack deflection and fiber pullout mechanisms when impacted. Some advanced tool heads are designed with functional gradient materials, with hardness gradually decreasing and toughness increasing from the cutting surface to the inside, achieving an optimized distribution of performance.Precise control of the heat treatment process is crucial to performance improvement. The application of low-pressure sintering technology enables cemented carbide to reach a density of more than 99.9% and a porosity close to zero. Subsequent hot isostatic pressing (HIP) treatment can effectively eliminate internal micro defects and improve material homogeneity. Specific heat treatment processes can also regulate the crystal structure of the cobalt phase, transforming from face-centered cubic (fcc) to hexagonal close-packed (hcp), thereby improving deformation resistance. Cryogenic treatment (-196℃) can stabilize the structure, release residual stress, and extend the service life of cemented carbide cutter heads by 20-30%.Geometry optimization is also important. Modern cemented carbide cutter heads are designed with computer-aided design and force distribution is optimized through finite element analysis. Innovative edge processing technologies, such as micro-chamfering and blunt radius control, can significantly reduce stress concentration during cutting. The self-sharpening design allows the cutter head to maintain an ideal geometric angle during wear and extend the effective cutting time. The fluid-dynamically optimized chip groove structure can reduce cutting heat accumulation and reduce the risk of thermal cracks.Practical applications show that cemented carbide cutter heads that use these technologies have improved wear resistance by more than 50% and impact resistance by 2-3 times in granite cutting tests. In the application of coal mine roadheader cutter heads, the service life has been extended from the original 80 hours to 150 hours, greatly reducing equipment downtime and replacement costs. With the development of material characterization technology and computational materials science, the performance optimization of cemented carbide tool heads is shifting from empirical trial and error to precise design, providing more reliable and efficient cutting solutions for industrial processing.
