The process of making PCD wire drawing die core generally includes the following steps:
1. Raw material preparation
Selection of PCD raw materials:
According to the performance requirements of the required PCD wire drawing dies, such as hardness, wear resistance, thermal stability, etc., select the polycrystalline diamond (PCD) raw materials with appropriate particle size, purity and binding agent content. o Preparation of die sleeve materials: Usually, stainless steel and other materials with good strength and corrosion resistance are used as die sleeves.
Preparation of die sleeve material:
usually choose stainless steel and other materials with good strength and corrosion resistance as the die sleeve, according to the design requirements processed into the appropriate size and shape.
2. PCD Sintering
Mixing and loading:
Mix PCD raw materials with appropriate amount of metal bonding agent (e.g. cobalt, etc.), and then load the mixed materials into the mold, to ensure that the materials are filled evenly and densely.
High-temperature and high-pressure sintering:
Put the mold sleeve with the material into the high-temperature and high-pressure equipment for sintering. Under the action of high temperature and high pressure, the diamond particles in the PCD raw material bond with each other under the action of binding agent to form dense polycrystalline diamond body, which is firmly bonded with the mold sleeve.
3. Mold core processing
Cutting: According to the size and shape of the required PCD wire drawing die core, the sintered PCD die blank is cut into suitable blanks using cutting equipment.
Laser Hole Punching:
Laser hole punching technology is used to create precise drawing holes in the PCD die core. Laser drilling provides precise control of the hole diameter, shape and location to ensure compliance with design criteria4
Grinding and Polishing:
Grinding and polishing equipment is used to grind and polish the inner holes and outer surfaces of the PCD cores to improve the surface finish of the cores, reduce the coefficient of friction, ensure that the metal wires pass through the cores during the drawing process, and to help improve the service life of the cores.
4. Post-treatment
De-cobaltization:
If the PCD cores contain cobalt as the binding agent, in order to improve the thermal stability and wear resistance of the cores, it is usually necessary to carry out de-cobaltization. A common method is acid leaching, where the cobalt is removed from the mold core by immersing it in an acid solution so that the cobalt reacts with the acid .
Cleaning and drying:
The PCD cores after cobalt removal treatment or other post-treatment are cleaned to remove acid, impurities, etc. on the surface, and then dried to ensure that the surface of the cores is clean and dry.
5. Quality Inspection
Dimensional accuracy testing:
Use measuring tools (such as calipers, micrometers, coordinate measuring machines, etc.) to measure the outer diameter, inner diameter, length, hole diameter, etc. of the PCD cores, to ensure that the dimensional deviation is within the tolerance of the design requirements.
Hardness testing:
Use hardness testing equipment to test the hardness of the cores. Hardness testing: Usehardness testing equipment to test the hardness of the cores.
Hardness testing:
adopt hardness testing equipment (such as Rockwell hardness tester, Vickers hardness tester, etc.) to test the hardness of PCD mold core to check whether its hardness is in accordance with the product standards and usage requirements.
Surface quality inspection:
Observe the surface quality of PCD cores through optical microscope, electron microscope and other equipments to check whether there are defects such as cracks, porosity, sand holes, etc., and evaluate whether the surface finish meets the requirements. Packing and storage: Pack the PCD cores in the warehouse.
Packing and storage:
The tested PCD cores are packed, usually with plastic film, carton and other packaging materials to prevent damage during transportation and storage. The packaged cores are put into the warehouse for proper storage, waiting for shipment and use
