Steel discs (often called strike plates) offer added flexibility when working with magnets. They can be used in place of a magnet in some applications because they make an ideal target for other magnets to attract to and attach with. This can dramatically lower your production or project expenses as steel discs cost significantly less than magnets.
Due to their ultra thin profile, these blank steel discs can be used to create a variety of magnetic catches, latches, packaging and box closure mechanisms – again, without the cost of an additional magnet.
As a result, these discs are ideal for a wide array of custom cabinetry creations, scrapbook attachments, door closures, sign and banner stays – as well as closure mechanisms on furniture, luggage, bags, holsters, wall-hangings, draperies and tarps.
For best results, we recommend that the steel disc be slightly larger than the attaching magnet in diameter.
You should also consider another difference that isn't reflected in the pull force or price. When you stick two magnets together, there are lateral forces that act to pull the magnets to center upon one another. This is not the case with steel discs.
Steel discs and magnets will not attempt to center themselves on their own when they are combined. Instead of drawing toward the center, the magnet will attach to any point on the steel object. This is ideal if you're making a latch and the magnet's position might change slightly. Despite the slight misalignment, the force will be roughly the same so long as the steel strike plate that is larger than the magnet.