The A36 carbon steel perforated sheet with staggered perforations meets American Society for Testing and Materials International ASTM A36 specifications, has an unpolished (mill) surface, and has been hot rolled. A36 carbon steel has low carbon content for good weldability and toughness, and bends to resist breakage under stress. The perforations are staggered in parallel diagonal rows.
Perforated metal sheets are created by punching a series of holes in a solid material. The holes are typically round, square, or slotted, but other patterns include hexagonal, Grecian, and cane. Holes are staggered (in parallel diagonal rows) or straight (in parallel vertical and horizontal rows). A sheet's perforation size, center spacing, and percent open area (ratio of open space to total space in a given area of expanded metal) will all affect the particle size and the amount of light, sound, air, and liquid that can pass through.