10 x’s greater tool life
A Zinc die’s tooling life can be more than 10 times longer than that of an aluminum die! Lower casting temperatures for zinc are easier on tools because they create minimal thermal shock and prolong die casting tool life. With dies costing upwards of $50,000 each, having a long lasting tool can represent a significant cost savings.
Superior thermal conductivity
Zinc is a better conductor of heat than Aluminum which makes it perfect for applications like heat sinks or electrical components. This means Zinc is able to absorb and dissipate the heat better than Aluminum.
Low melting point = cost savings
Zinc melts at 787.2°F whereas Aluminum melts at 1,221°F. This gives Zinc an advantage because casting can use a process called “Hot Chamber” casting which is quicker as well as being less costly than “Cold Chamber” methods.
Faster cycle times = better pricing
Using the Hot Chamber process also gives Zinc a major advantage over Aluminum because the hot chamber process goes so much quicker than Cold Chamber. In cold chamber, Aluminum needs to be manually poured into the die either by hand or using a robot. Using hot chamber casting, the molten liquid zinc is shot into the die using a highly pressurized “plunger” which systematically shoots the zinc through the die.
Thinner wall stock
ZAMAK alloys have exceptional casting fluidity. It’s possible to cast walls in ZAMAK as thin as .25 inches. Thinner, stronger walls results in smaller and lighter products with lower costs.
Less machining required for tight tolerances
Zinc die casting has tighter tolerances than Aluminum or plastic die casting, which often eliminates the need for additional machining. When no additional machining is needed, it’s called “Zero Machining” manufacturing. This is one of the major advantages of Zinc die casting.
Superior for decorative finishing
ZAMAK alloys have a better surface for finishing because Zinc comes out of casting with a smoother skin. Because Aluminum has to be so much hotter than Zinc, the thermal shock from being put in a die produces a part with a surface that can be more pitted. Chrome finish amplifies every defect in a part, which makes Zinc much easier to finish compared to Aluminum. Zinc die casts can be easily polished, plated, painted, chromated or anodized.
Zinc alloys are some of the strongest and toughest materials for die casting. Neither plastic, gray cast iron, or Aluminum withstand impacts as well as Zinc alloys do.
If you do choose Aluminum
Sometime aluminum is the best choice. To learn more about aluminum die casting, please contact Texas Diecast Company.