The quality vacuum nitrided SKD61 mold thimble has the […]
The quality vacuum nitrided SKD61 mold thimble has the characteristics of hardness, good toughness and wear resistance, but no matter how good the thimble is, it may be deformed during use. Why? How to reduce this phenomenon?
1.the symmetrical mold can consider the deformation problem of the thimble of the mold according to the size, shape and height of the mold cavity. When the wall of the mold is thin and the height is small, it is easier to harden. At this time, the tissue stress may play a leading role, and therefore, the cavity tends to expand. On the other hand, if the wall thickness and height are large, it is not easy to be hardened. At this time, thermal stress may play a leading role, and therefore, the thimble of the mold may be deformed.
2.the problem of asymmetric die thimble deformation is also the result of the combined effects of thermal stress and tissue stress. For example, for a thin-walled thin-walled mold, since the mold wall is thin, the internal and external temperature difference during quenching is small, and thus the thermal stress is small; but it is easy to be hardened and the tissue stress is large, so the deformation tends to expand the cavity.
3.when the shape of the mold cannot be changed, in order to reduce the deformation of the thimble of the mold, some other measures can be taken. The general consideration of these measures is to improve the cooling conditions so that the parts can be uniformly cooled; in addition, various enforcement measures can be assisted to limit the quenching deformation of the thimble.