Standard and Flattened Expanded Metal

Both standard and flattened expanded metal types bring their own distinct advantages and disadvantages.

Advantages of standard expanded metal include:

• Greater structural strength because strands distribute weight more evenly
• May provide directional flow
• Higher-grade gripping properties, making it superior for walkways
• Durable and long-lasting

Disadvantages of standard expanded metal include:

• Not as aesthetically pleasing as flattened expanded metal
• Heavier and denser
• Delivery may cost more due to greater weight

Advantages of flattened expanded metal include:

• About 5 percent lower material weight
• Burnished surface offers a smoother, sleeker appearance than standard expanded metal
• Thinner, flatter, and lighter, making it great for fencing material
• Corrosion-resistant
• Often less expensive than other expanded metals

Disadvantages of flattened expanded metal include:

• Not as strong as standard expanded metal
• Poorer grip, making it a less viable choice for walkway construction

The construction industry uses most expanded metal — both standard and flattened. Food processing, automotive, aerospace, pharmaceutical, and telecom industries also employ this metal type.

Standard expanded metal is often used in grates, ramps, and other applications where traction is important. The raised surface of the metal provides good grip for tires and shoes. Standard expanded metal makes excellent walkways, staircases, grills, security doors, racks, and shelves. Standard expanded metal also makes great strainers for fluid, air, or even industrial kitchens.

Flattened expanded metal is often used for fencing, railings, and ceiling tiles.

All expanded metal has been fed through an expanded metal mesh machine. Flattened expanded metal has also been cold rolled.

Consequently, the metal grade used to create expanded metal has to be easy to machine. Typically, manufacturers use grade 316 steel, which is a low-carbon austenitic type of steel known for its toughness and durability.

Expanded metal is never easy to weld because you are trying to attach a thin plate to a thick plate. It’s easy for your arc to burn up the thin plate, which is usually your expanded metal sheet. To avoid this problem, many welders use TIG instead of MIG welding so they can control their power and avoid penetrating the thinner sheet.

Successfully welding expanded metal requires training the heat on the thicker piece of material and pushing the puddle on top of the expanded metal. With expanded metal, you can’t run a long bead, so you are essentially doing spot welding. You may or may not need to weld each prong of the expanded metal separately depending on the outcome you need.

The heat treatment of expanded metal is a process by which the metal is heated and then cooled in order to change its physical and/or chemical properties. The most common reason for heat treating expanded metal is to increase its strength and hardness. Depending on the type of expanded metal, the heat treatment process can vary.

For example, standard expanded metal is typically heat treated using a process called annealing, while flattened expanded metal is sometimes heat treated using a process called tempering.