During the experiment, the matching between the injection green and the ceramic bearing plate is an interference factor in the thermal process. When the surface of the ceramic bearing plate is too smooth (Ra<3 μ m) After sintering, the spur gear will stick to the ceramic bearing plate, which is not easy to take off, and is easy to damage the ceramic bearing plate. After analysis, it is found that after adding niobium (Nb), due to the carbon capture reaction of niobium, the oxide and carbide deposited on the ceramic bearing plate will interact, resulting in the adhesion of the ceramic plate. The 420 or 440 series stainless steel with niobium also has a similar phenomenon, and there are few related records in the past, However, most MIM manufacturers with similar production experience have the same problems.
After consultation with the manufacturer, measures such as increasing the surface roughness and grooving can be taken before the ceramic plate leaves the factory to improve the degreasing and exhaust process and effectively reduce the sticking phenomenon.
In addition, high-precision MIM spur gear products are not suitable for magnetic polishing or roller grinding. Gravity impact and excessive collision and friction will cause spur gear shape distortion, tooth tip damage, resulting in spur gear meshing noise and performance degradation.