What is Zinc Die Casting?

Written By Rachel Novak

As I entered into the world of Snap Hooks and Rigging Hardware a key point to my education and learning curve was understanding the terminology and processes that are used with our product line.  For instance Zinc Die Casting.  What was that?  Veterans of the industry may be well aware and versed with the term and process but for those of you who may not fully understand, I hope my research will help explain.

Zinc Die Cast snaps hooks in our product line are made in this manner.  It’s a process in which molten metal is placed under high pressure into molds or “Dies”.    This process is very popular because of the variety of shapes and molds that can be created as well as the volume that can be reproduced with excellent results.  The outcomes can be either left in their raw form or finely polished for a more finished look.  For example many bathroom or kitchen faucets are plated zinc die casted.

The history of Die Casting goes back to the mid 1800s.  Sturges in 1849 was awarded a patent for the first manually operated machine for cast printing.  By 1892 after other shapes and purposes were quickly developed and the concept and practice took off in industry and by 1900 mass production of many different parts began.

Advantages to Zinc Die Casting:

  • Efficient & Economical process offering a large variety of possible shapes & forms.
  • High Speed Production
  • Dimensional Accuracy & Stability
  • Strength & Weight
    • thin castings reduce the amount of material needed thus weight involved
    • casting is stronger than their plastic counterparts and the lack of welding or joined pieces adds to the overall strength of the finished product.
  • Multiple finishing techniques available
  • Simplified Assembly

The Die Casting process began with the use of  the alloys tin and lead, magnesium and copper alloys quickly followed, and by the 1930s, many of the modern alloys still in use today became available.  The process evolved from the low pressure injection casting to a modern high pressure injection of 4500 pounds per square inch.   The modern processes are capable of producing high integrity, net casting shape with excellent finish surfaces.

For additional information on the process of Zinc Die Casting I found the North American Die Casting Association’s website to be extremely informative and useful.  (www.diecasting.org)