Hot Keywords: Sol precision castings
Die Casting time includes filling, pressing and precision die-casting mold casting in the residence time of holding. It is the pressure, speed, temperature, these three factors, plus the consolidated results of the physical properties of liquid metal, casting structure (especially wall thickness), mold structure (especially the gating system and overflow discharge system) and other aspects.
1, holding pressure time. Holding pressure time depends on the material and wall thickness precision casting. High melting point, crystallization temperature range Japanese thick-walled castings, holding pressure time should be longer. Crystallization temperature range of small and thin walled castings, holding pressure time can be shorter. If the holding pressure time is less, it could easily lead to shrinkage. But holding pressure time is too long, will not achieve significant results, it could easily lead to removal of excess material difficulties vertical die casting machine. From the liquid metal fill the cavity to the gate completely solidified, the continued duration of the injection plunger under the action called holding pressure time. Holding pressure time is the role of the injection plunger has enough time passed to the pressure of solidified metal casting under pressure to ensure the crystallization, strengthen feeding, in order to obtain a dense tissue.
2, open-time. After holding pressure should remove mold precision casting products. From the end of the injection die casting mold open time called time. Enough time to allow the casting mold in the mold will have a certain strength, without deformation during mold opening and ejection or crack. Meat mold time is too short, the strength is still relatively low at the time of casting on the release, casting deformation. Low intensity alloy may also be due to expansion of internal pores produce surface blistering. But mold too long, the temperature is too low precision casting products, shrink large, and the top of the casting core pulling resistance is also large, hot brittleness of the alloy castings also cause cracking, but also reduce the productivity of the casting.
3, the filling time. When the die-casting liquid metal into the die-casting mold cavity from the beginning to the time required until full cavity called filling time. The length of time depends on casting to fill the volume of the size and complexity. Large and simple products, filling time is relatively longer, complicated and thin wall castings to segment some of the filling time. Fill time adjustment method and adjustment method is similar to filling speed. http://www.cnwxyszj.com