Research On The Visualization Measurement Of Temperature Field Of Polycrystalline Diamond

PDC (Polycrystalline Diamond Compact) is one kind of superhard composites which is made from diamond micro-powder and tungsten carbide by sintering process under high temperature and high pressure. The diamond crystal assumes disorderly arrangement, isotropism in PDC, and overcomes the defects such as monocrystal volume too small, aeolotropy and so on. As result of the advantages of PDC both has high hardness, high elastic ratio of the diamond and good impact toughness of the tungsten carbide, and has the characteristics as high heat conductivity, low heat expansion rate etc, the PDC widely used in the field of machine-finishing, petroleum geological drilling and other areas.In the production of PDC, it is very important to temperature control in the course of sintering of Polycrystalline Diamond Compact, it will influence final product quality directly. Sintering temperature is too high or too low possibly creates PDC less than burning or incineration, therefore a timely and effective monitoring to the Polycrystalline Diamond Compact is necessary. For a long time, the main way to monitor Polycrystalline Diamond Compact temperatures field is by values of temperatures transducer and experiences of human to judge, this way is not reflection directly, requiring too much work to do, low efficiency and over-depended on experience, the quality of product will be affected in the end. So, to take the more effective measure for monitoring and controlling become an important research direction.Because for the particularity of PDC production industry, We adopt visualization measure technology to measure PDC temperatures field. This dissertation uses the heat transfer study knowledge, has established the interior temperature field model with the finite difference method. The simulation research proof, the model can accurately forecast the PDC interior temperature field data.This dissertation take the artificial diamond hexahedron press synthesizes PDC as the experimental object, has researched and developed measure system of PDC temperature field. The system was made up of embedded data acquisition/controller that based on RS485 bus and PC Computer. The embedded data acquisition/controller was realized by 51 single chip microcomputer, adopted C51 language to write the procedure of the data processing; PC as supervision and control host computer, adopted graph language LABVDEW to compile software, which have some functions such as display temperature field ,power parameter curve, datasheet, save, print etc. Adopt Fuzzy—PID control algorithm realized power continuous and accurate control of diamond press system. The temperature field visualization was on the foundation that has attained PDC interior temperature field mathematical model, use Intensity Graph control in LabVIEW realized function. Practice indicates, the system has reached the required function and technical index, obtained good effects of measurement, display and control.