Powder molding mold in the injection molding time, more often in fact is the phenomenon of cracking, and in terms of cracking, it is actually more common plastic products a shortcoming, the powder molding mold cracks The first factor is actually because of stress caused by deformation. First of all, it is in fact to pay attention to the residual stress and external stress and the external environment of the stress deformation occurred.
Powder molding die in the injection molding when faced with the residual stress caused by the phenomenon of cracks, for the remaining stress, that is, there will be overfilling, mold release and the formation of metal inserts defects. As a result of the phenomenon of cracking under the condition of overfilling, it is because the solution pressure loss is the smallest, and it is precisely because of this, when the crack first occurred in the straight gate adjacent Time, we actually have to pay attention should be to think about the use of multi-point distribution point gate, side gate and its handle-type gate method.
Then, when it comes to the powder molding die in the injection molding when the crack phenomenon, to ensure that the resin is not differentiated or not deteriorated under the premise, to a large extent, it is necessary to pay attention to the appropriate progress of the resin temperature Drop the melt viscosity, improve its mobility, together with the time, that is, can drop the injection pressure to reduce the stress.
Under normal circumstances, the mold on the mold mold mold temperature is relatively low when it will simply stress, should be appropriate to improve the temperature. But when the injection speed is relatively high, even if the mold temperature on the lower, it is to a large extent that can reduce the occurrence of stress.
Finally, when it comes to the powder forming mold on the crack phenomenon, in the injection and packing time is relatively long, it is in a very large extent, it will be stress, it is appropriate to shorten or to carry out Th Times after the pressure switch will be better after the switch. Also said in time, in this case, to a certain extent, it is to avoid the phenomenon of powder molding mold cracks.