Tungsten carbide is an alloy material made from hard compounds of refractory metals and a binder metal through powder metallurgy.Due to its high hardness, wear resistance, strength, and good toughness, it is frequently used to manufacture rock drilling tools, mining tools, drilling tools, measuring tools,etc. It has wide applications in the oil and gas, chemical, engineering machinery, and fluid control industries. Tungsten carbide is a material produced by pressing using powder metallurgy. Today, we'll introduce some common problems during the suppressing process and briefly analyze their causes.
1. A common type of defect in cemented carbide pressing is delamination.
Delamination occurs along the edges of the suppressed block, forming a neat interface at a certain angle to the pressed surface. Most delamination starts from the edges and extends into the pressed block. The cause of delamination is the elastic internal stress or elastic tension within the pressed block. For example, low cobalt content in the mixture, high carbide hardness, finer powder or granules, insufficient or unevenly distributed forming agent, excessively wet or dry mixture, excessive pressing pressure, excessive weight, complex block shape, poor mold finish, and uneven worktable can all cause delamination.Improving the strength of the block and reducing internal stress and elastic shrinkage are effective methods to solve delamination.
2. Granularity can also occur during cemented carbide suppressing.
Due to excessively large pore sizes in the compact, these pores cannot completely disappear during sintering, resulting in numerous residual pores within the sintered body. Excessively hard or coarse granules, excessively loose material packing, uneven distribution of loose granules in the mold cavity, and low weight can all cause granulation.
3. Cracks are a common defect in cemented carbide suppressing.
Irregular localized fractures in the block are called cracks. This is because the tensile stress inside the block exceeds its tensile strength. The tensile stress inside the block originates from elastic internal stress. Factors influencing delamination also affect cracking. The following measures can be taken to reduce crack formation: extending holding time or applying pressure multiple times, reducing pressure, reducing unit weight, improving mold design and appropriately increasing mold thickness, accelerating demolding speed, increasing molding agent, and increasing material bulk density.
The entire cemented carbide production process is crucial. OSTON CARBIDE specialize in tungsten carbide solution for worldwide customers,for any questions regarding cemented carbide production, please feel free to contact us.
