Stainless Steel
Stainless Steel & Special Alloys
Growth in world consumption of stainless steel has been following a steady upward course for many years, underlining not just the popularity of this versatile alloy, but its remarkable range of important properties. It has a high strength-to-weight ratio, is extremely resistant to corrosion, wear and heat, and is readily formed or welded. It is an excellent environment- and maintenance-friendly material. Moreover, it is beautiful to look at.
Stainless steel is essential in the construction of all types of chemical processing applications. It is developing ever-wider uses in the construction, automotive, health, environmental and transport industries. Its increasing use in household and restaurant products, from kitchen sinks to cutlery is more and more evident in our everyday life. A steady supply of quality secondary material is vital to underpin continuing growth in the evolving market for stainless steel. It is also of critical importance in conserving reserves of some especially valuable metals, for the "magic" of stainless steels stems from alloying combinations with elements such as nickel and chromium. This sector of recycling is one of continuous development.
The basic grades of stainless steel form an important part of a much broader family of alloys designed to provide optimum performance under severe environmental and chemical conditions, along with remarkable strength and stability at high temperatures. Tungsten, molybdenum, cobalt, titanium and vanadium are among the major alloying metals used to meet the toughest demands made by engineers in the aerospace, chemical and other high performance industries. Like nickel and chromium, these metals are costly, and occur in limited mine deposits in only a few parts of the world. Recycling is therefore of particular importance, for without it the law of supply and demand would inevitably make many of these metals prohibitively expensive.
Most of these alloys have a very similar appearance, but they are designed to serve quite different purposes and therefore cannot be mixed. Great expertise is needed in recycling, and the skill of the processor is matched today by sophisticated technology for separating and preparing each type of alloy for remelting.
Some of the remelting processes employed depend on extremely high levels of purity in the secondary material, and scrupulous processing by the recycler is therefore essential.
In all areas of special alloy recycling, positive identification of the elements present, and of their percentages, in a wide range of complex alloys are indispensable. Successful recycling depends on the use of sophisticated scientific instruments - such as the X-ray spectrometer - combined with processing skills and meticulous management, in order to meet rigid specifications stipulated by the consuming market.
