Expanded metal sheet is made by first creating multiple slits in the sheet, and then stretching the sheet. The stretching creates a unique diamond pattern opening with one of the strands protruding at a slight angle. These raised strands can be flattened later in the process if desired. As you can see this process creates no waste (thus keeping down production costs) and it can add structural strength to the product.
Expanded Metal is produced from solid sheets or plates of carbon, galvanized and stainless steel, as well as aluminum and a variety of alloys of copper, nickel, silver, titanium and other metals. Because expanded metal is made from a solid sheet of metal, and it is not woven or welded – it can never unravel. To produce expanded metal, a sheet or plate is simultaneously slit and stretched.
This process expands the cuts into diamond shaped holes of uniform size and shape. Because no metal is lost in the expanding process, expanded metal is cost effective and saves energy by conserving material and allowing the fabrication to go further and do more. When choosing expanded metal for your fence application, you will need to determine which style or diamond size is best for your application. Expanded metal designations are indicated by SWD (the measurement on the short way of diamond), while the second number may specify the gauge of metal, the weight per hundred sq. foot, or have some other significance.