Zinc die casting process introduction
Zinc alloy die casting process can be divided to hot chamber die casting and cold chamber die casting. The difference between them is the different die casting machines they are using. Generally speaking, hot chamber die casting machine is much suitable for small and light zinc products, while cold chamber die casting machine for weight and large zinc die casting products.
All of die casting machines Parison owned are cold chamber die casting machines. And we indeed prefer to casting a little larger zinc products. Besides we are willing to help outsource small and light zinc die cast products from other hot chamber die casting foundries. Our precision machining factory also out sources raw die castings of zinc alloy for further precision machining.
Cold chamber die casting of zinc alloy
Cold chamber die casting process need the molten zinc alloy to be ladled into the cold chamber, then inject it into the die cavity. The molten zinc alloy is kept in electronic furnace or other kinds of furnace can be protected from reaction with atmosphere. Thus the cold chamber die cast products can have much purer alloy. Furthermore, the cold chamber die casting process can have low and steady deviation, that is to say high precision of die casting.
The only limitation of cold chamber die casting machine is that it's not suitable for small die casting. The main reason is the excessive weight of spure and running system compared with the costing itself. The several times heavier spure and running system have to be remelted or as waste. It is much more costly than hot chamber die casting process.
Hot chamber die casting of zinc alloy
Hot chamber die casting process was invented earlier than cold chamber die casting process. It is preferable for casting zinc, copper and lead alloys. The hot camber die casting process is much more suitable for small size die cast products. And commonly the hot chamber die casting process have a much swifter speed than cold chamber die casting process.
Hot chamber die casting process is not suitable for large size die cast products. The more times flowing of molten alloy will react with oxygen within atmosphere. And for larger parts, the hydraulic shot cylinder have to press more than one time, as leads to different time solidification and bad inner structure of casting.
Zinc die casting technique database
- Zinc die casting alloy designation
- Zinc die casting tolerance designation table
- Zinc die casting process technology
FAQ's of Zinc die casting process
- what is Zinc die casting process?
- What is application of zinc die casting products?
- what kinds of post treatments can be available for zinc die casting products?
- what other casting process can be available for zinc alloy?
Illustration of hot chamber die casting process
In a hot chamber die casting process, the molten alloy is pressed into die cavity through gooseneck, after the cavity is filled full, the extra molten alloy flows back to the furnace along with pressure release. For small size of die cast product, the hydraulic shot cylinder can finish injection at once, however if the casting is much larger and heavier, it have to operate twice or more times. Twice injection is not good for casting, that can leads to different rate of solidification and bad casting crystal.
After injection, the molten alloy filling the cavity cools with assistance of water cooling system and shape the desired features. While the extra alloy in gooseneck flows back to the furnace. Thus the hot chamber die cast raw part have much smaller sprue system and swifter casting speed than hot chamber die casting process.
Hot chamber die casting process is preferable for zinc, copper and lead die casting. One of the reasons is those die casting products are always not very heavy and large. And such alloys have worse fluidity than aluminum alloy.
