Research on the diamond tool wear life

Diamond material can be divided into natural diamond and synthetic diamond . Natural diamond has the highest hardness of the material of nature and thermal conductivity . In recent years, a variety of methods and the development of protective atmosphere by chemical mechanism of diamond grinding tools brazed diamond tool manufacturing technology makes it relatively easy , so that the cutting tool in the field of ultra-precision mirror widely used. 1950s achieved using high temperature and pressure techniques of synthetic diamond powder , the 1970s produced the diamond cutting tool that is based polycrystalline diamond (PCD) tools. PCD grains were arranged in a state of disorder , non- directional , and thus uniform hardness . PCD cutting tools with high hardness (8000 ~ 12000HV), high thermal conductivity , low thermal expansion coefficient , high elastic modulus and low coefficient of friction , the blade is very sharp , high-speed machining of various non-ferrous metals and wear strong performance of non- metallic materials such as aluminum, copper, magnesium and their alloys , tungsten carbide, reinforced plastic materials, metal matrix composites, wood composites. Currently being researched and developed chemical vapor deposition (CVD) diamond primarily in two forms : one is deposited on a substrate of thin film thickness of less than 30μm (CVD film ) ; another substrate- deposited thickness up to 1mm thick layer of diamond film (CVD thick ) .
    Three main diamond tool materials --- PCD, performance comparison results and synthetic single-crystal CVD diamond thick as : Maximum PCD welding , mechanical grinding, and the fracture toughness, abrasion resistance and quality of the cutting edge center, corrosion worst ; CVD thick best corrosion resistance , mechanical grinding resistance, edge quality , fracture toughness and abrasion resistance centered , weldability worst ; edge quality synthetic single crystal diamond , anti- the best wear resistance and corrosion resistance , weldability, mechanical grinding and fracture toughness worst. Currently, the diamond cutting tool is a high speed (2500 ~ 5000m / min) Aluminum ideal tool material , but in high-speed cutting of steel and its alloys Shique wear faster , which is mainly due to the wear mechanism of carbon and iron with greater affinity effect, especially at high temperatures the diamond easily react with the iron , it is not suitable for the cutting of steel and their alloys . High-speed cutting tool wear life.
    High-speed cutting tool wear should determine a reasonable lifetime ( limit ) based on processing methods and processing requirements. Impact of high-speed cutting tool wear life of many factors , such as the material of the workpiece material and tool matching , cutting mode , tool geometry , cutting parameters , coolant, tool wear and vibration have a significant impact on the life of its laws and specific effects of cutting conditions , the effect should be to determine the impact of various factors on the tool wear life by cutting tests . High-speed machining hardened steel under ( cutting feed rate 0.1mm / r, cutting depth 0.2mm, blunt knives standard VB = 0.2mm) , respectively, using the same cutting conditions P10 carbide tools , ceramic tools and CBN tooling when AISI 4340 workpiece material ( hardness 60HRC), a minimum operating life of carbide tools , this is due to the high hardness of the material of the workpiece , resulting in cutting forces and high temperatures during processing , resulting in rapid wear of the cemented carbide cutting tools , and even peeling fracture damage. Ceramic knives and working life with CBN cutting tool to improve and increase the maximum when you start lowering the threshold . The reason for this may be increased when the cutting tool to increase the thickness of the adhesive layer , a protective film is formed , will help reduce wear of the tool , thereby increasing the tool life ; when cutting , the tool is further improved surface layer will soften the workpiece material is easy to wear off in the hard particles , thus exacerbating the tool wear , resulting in rapidly reducing the diamond tools life.