Many manufacturers consider slabs with a thickness between 0.25inches and 0.5inches to be plates. This common stock form is occasionally used as the end product, but more typically will undergo further manufacturing processes.
Stainless steel plates are ideal for a long list of industrial parts manufacturing processes such as welding, drilling, machining, shearing and forming. Building, construction, automotive, electronics, aerospace, marine, electronics, chemical processing, residential and many other industries commonly use stainless steel plates for components ranging from pipelines to protective plating to oil rigs.
Such applications favor stainless steel plate for more than its workability. The material is well known for its superior resistance to rust, wear and corrosion even in harsh environments. Additional qualities of stainless steel plate will vary depending upon the specific grade of material used, but include tensile strength, high ductility, strength to weight ratio, impact and heat resistance, longevity and hardness. Each of these should be considered with regard for the intended use of stainless steel as should thickness, gauge thickness, overall width and overall length.
Like all stainless steel products, plates begin either as recycled or raw materials which must be heated or melted to their re-crystallization temperature, allowing the mixture to homogenize while burning out any unwanted impurities. Though the specifics vary among the dozens of grades of stainless steel, each is composed primarily of iron ore with at least 10% chromium.
The high concentration of chromium is what gives stainless steel its name and several of its most advantageous qualities. The alloyed chromium forms a “passivation” layer of chromium oxide on the surface of the stainless steel plate or other stainless product. This protective layer is what prevents staining, wear and corrosion. Smaller amounts of carbon, nickel, molybdenum, silicone and aluminum are present in various combinations.
Once thoroughly heated the material is rolled into sheets. Layers are compressed and forged into a single piece that has the desired dimensions. An alternative to this hot rolling process, steel plates may be made through cold rolling which instead forces cooled stainless steel ingots through progressively thinner rollers until the desired thickness is achieved.
Steel service centers will often perform secondary processes such as sawing, heat treating, stress relieving, annealing, normalizing, cutting, testing, milling, deburring, straightening and more to deliver sheets as close to the end product as possible.