(1) The asymmetrical inlay of the diamond die blank and the die steel sleeve, and the uneven distribution or gaps of the sintered cemented carbide steel sleeve can easily lead to U-shaped cracks during wire drawing;
(2) During the laser drilling process of the diamond die blank, the sintering traces are not cleaned or unevenly heated, which will cause the metal catalysts and bonding agents in the diamond layer to gather together, which will easily lead to pits in the diamond wire drawing die during the wire drawing process;
(3) The mold hole design is unreasonable, the inlet lubrication area opening is too small, and the setting area is too long, which will cause poor lubrication, resulting in mold wear and even chipping.
(1) The drawing surface shrinkage is too large, causing cracks or breakage of the diamond wire drawing die. Most of the cracks or broken cracks are caused by the release of internal stress. In any material structure, the existence of internal stress is inevitable. The internal stress generated during wire drawing can enhance the diamond microcrystalline structure, but when the drawing surface shrinkage is too large, it cannot be lubricated in time, and the temperature rise will cause part of the material on the surface of the diamond wire drawing dies to be removed, and the stress on the microcrystalline structure will greatly increase, making it easier to crack or break.
(2) The drawing axis of the wire rod is asymmetrical with the center line of the die hole, resulting in uneven stress on the wire rod and the wire drawing die, and the impact generated by mechanical vibration will also cause high stress peaks on the wire rod and the drawing wire die, both of which will accelerate the wear of dies.
(3) Factors such as uneven wire hardness caused by uneven annealing can easily cause premature fatigue damage to the diamond wire drawing die, forming annular grooves, and aggravating die hole wear.
(4) The wire surface is rough, and the surface adhesion of oxide layer, sand or other impurities will cause the dies to wear out too quickly. When the wire passes through the die hole, the hard and brittle oxide layer and other adhering impurities will cause the wire drawing die hole to wear quickly and scratch the wire surface like abrasives.
(5) Poor lubrication or the lubricating oil contains metal debris and impurities that cause mold wear. Poor lubrication will cause the surface temperature of the diamond die hole to rise too fast during wire drawing, and the diamond grains will fall off, resulting in damage to the die. When the lubricating oil is not clean, especially when it contains metal chips that fall off during drawing, it is very easy to scratch the surface of the mold and the wire.