Effect of different hardness on polishing process：

The increased hardness increases the difficulty of grinding, but the roughness after polishing decreases. As the hardness increases, the polishing time required to achieve a lower roughness increases accordingly. At the same time, the hardness increases and the possibility of excessive polishing decreases accordingly.

density:

The purity of the material, the particle size of the powder and the sintering density are also the key factors that affect the polishing. The material density during sintering needs to be controlled within a reasonable range in order to achieve the polishing effect. Improper density control will cause defects such as sand holes and pits

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