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(1) Effect of powder properties

The powder with large hardness, small plasticity and large friction property has poor pressing property, and can be appropriately improved by adding a lubricant or a molding agent; when the powder has low purity and high oxygen content, the pressing property is poor, and the reduction of the raw material powder can be overcome; The fine-grained or coarse-grained powder, as well as the shape-regulating powder, are not ideally pressed, and the mixed-size powder and the powder having a complicated particle shape can improve the pressability.

(2) The impact of the pressing process

The smoother the surface of the forming mold, the higher the hardness and the greater the rigidity, the more favorable the density and uniformity of the bad body; the density of the green body by two-way pressing is higher than that of the one-way pressing, and the uniformity; the lower the pressing speed, The longer the holding time, the higher the density of the blank, which is especially important for large-sized or complex-shaped grinding tools.