strategy 1: Matching the cutting tool material with the mechanical properties of the work piece<\/strong><\/p>\n\n\n\nThe mechanical property matching problem between the cutting tool and the machined object mainly refers to the mechanical property parameters such as the strength, toughness and hardness of the tool and the workpiece material. Tool materials with different mechanical properties are suitable for machining workpiece materials.<\/p>\n\n\n\n
1. The hardness sequence of the tool material is: diamond tool > cubic boron nitride tool > ceramic tool > hard alloy > high speed steel.<\/p>\n\n\n\n
2. The bending strength order of the tool materials is: high speed steel > hard alloy > ceramic tool > diamond and cubic boron nitride tool.<\/p>\n\n\n\n
3 The toughness order of the tool materials is: high speed steel > hard alloy > cubic boron nitride, diamond and ceramic tools.<\/p>\n\n\n\n
High hardness workpiece materials must be processed with higher hardness tools. The hardness of the tool material must be higher than the hardness of the workpiece material. Generally, it is required to be above 60HRC. The higher the hardness of the tool material, the better its wear resistance. For example, when the amount of cobalt in the cemented carbide increases, the strength and toughness increase, the hardness decreases, and it is suitable for rough processing; when the amount of cobalt decreases, the hardness and wear resistance increase, which is suitable for finishing.<\/p>\n\n\n\n
Tools with excellent high temperature mechanical properties are especially suitable for high speed machining. The excellent high temperature performance of ceramic tools enables them to be cut at high speeds, allowing cutting speeds to be 2 to 10 times higher than cemented carbides.<\/p>\n\n\n\n
Strategy 2: The cutting tool material should match the physical properties of the machined object<\/strong><\/p>\n\n\n\nTools with different physical properties, such as high-speed steel tools with high thermal conductivity and low melting point, ceramic tools with high melting point and low thermal expansion, diamond tools with high thermal conductivity and low thermal expansion, are suitable for processing workpiece materials. When machining a workpiece with poor thermal conductivity, a tool material with better heat conductivity should be used to allow the cutting heat to be quickly transmitted to lower the cutting temperature. Due to the high thermal conductivity and thermal diffusivity of diamond, the cutting heat is easily dissipated and does not cause large thermal deformation, which is especially important for precision machining tools with high dimensional accuracy.<\/p>\n\n\n\n
1. Heat resistance temperature of various tool materials: 700~800\u00b0C for diamond cutters; 1300\uff5e1500\u00b0C for PCBN cutters; 1100\uff5e1200\u00b0C for ceramic cutters; 900\uff5e1100\u00b0C for TiC(N) based cemented carbides; WC base The ultrafine grained cemented carbide is 800 to 900 \u00b0 C; the HSS is 600 to 700 \u00b0 C.<\/p>\n\n\n\n
2. Thermal conductivity sequence of various tool materials: PCD>PCBN>WC-based hard alloy>TiC(N)-based cemented carbide>HSS>Si3N4-based ceramic>A1203-based ceramic.<\/p>\n\n\n\n
3. The order of thermal expansion coefficient of various tool materials: HSS>WC based hard alloy>TiC(N)> A1203 based ceramic>PCBN>Si3N4 based ceramic>PCD.<\/p>\n\n\n\n
4. The order of thermal shock resistance of various tool materials: HSS>WC-based cemented carbide>Si3N4-based ceramic>PCBN>PCD>TiC(N)-based cemented carbide>A1203-based ceramic.<\/p>\n\n\n\n