Determine the material of the tool according to the machining type and workpiece material. It is a common knowledge in the whole machining industry to match tool materials with workpiece materials. But not everyone knows how many conditions this so-called match will satisfy. Next, we will introduce ‘how tool materials and workpiece materials can match mechanical, physical and chemical properties’.
How do the mechanical properties of tool materials and workpieces match?
The mechanical properties are mainly designed for the strength, toughness and hardness of the tool and workpiece. All kinds of tool materials are arranged in order of bending strength from strong to weak: high-speed steel, hard alloy, ceramic tool, diamond and cubic boron nitride tool. In order of toughness from high to low: high speed steel, hard alloy, cubic boron nitride, diamond and ceramic tool; In order of hardness from high to low: diamond tool, cubic boron nitride tool, ceramic tool, hard alloy and high speed steel.
Due to the difference in mechanical properties, the tool can meet the processing requirements of various workpieces. The hardness of the tool must be higher than that of the workpiece processed by it, so the workpiece material with high hardness must be processed with a higher hardness tool. Generally, the harder the tool material is, the better its wear resistance will be, but the strength and toughness will be affected. Tools with high hardness and high abrasion resistance are generally arranged for rough machining, while those with lower hardness are generally used for precision machining.
How do the physical properties of tool materials and workpieces match?
The physical properties mentioned here mainly refer to the thermal conductivity, melting point and thermal expansion rate of materials and other parameters.
The thermal conductivity of the cutting tool should be complementary with workpiece, when the poor thermal conductivity of workpieces, be sure to use strong thermal conductivity of knives, cutting heat derived in a timely manner, such ability to maintain the size of the cutter and workpiece precision. Various cutting tool materials are arranged in order of high to low heat resistance: cubic boron nitride, ceramic, titanium carbide, WC ultrafine grain carbide, diamond and HSS. According to the order of high to low thermal conductivity: PCD, cubic boron nitride, WC base cemented carbide, titanium carbide base cemented carbide, HSS, Si3N4 base ceramics and A1203 base ceramics; According to the order of thermal expansion coefficient from large to small: HSS, WC base cemented carbide, titanium carbide base cemented carbide, A1203 base ceramics, PCBN, Si3N4 base ceramics and PCD; According to the order from strong to weak thermal shock resistance: HSS, WC base cemented carbide, Si3N4 base ceramics, cubic boron nitride, PCD, titanium carbide base cemented carbide and A1203 base ceramics.
How do the chemical properties of tool materials and workpieces match?
Chemical properties include whether the tool has chemical affinity with the workpiece, the phenomenon of chemical reaction, diffusion and dissolution. If this happens, the tool does not match the material. Various tool materials are arranged in the order of high to low bonding temperature with steel: cubic boron nitride, ceramic, hard alloy and HSS; According to the order of oxidation resistance temperature from high to low: ceramic, cubic boron nitride, hard alloy, diamond and HSS; According to the order of diffusion strength of steel from large to small: diamond, Si3N4 base ceramics, cubic boron nitride and A1203 base ceramics; According to the order of diffusion strength from large to small for titanium: A1203 base ceramics, cubic boron nitride, SiC, Si3N4 and diamond.
In order to better solve the problem of workpiece materials and tool equipment materials. Our drill bit grinding machines provide various materials of grinding wheels for different materials of cutting tools.
