Q. What is stainless steel?
A. Stainless steel is the generic name for a number of different steels used primarily because of their corrosion resistance. All stainless steels share a minimum percentage of 10.5% chromium. It is this element that reacts with the oxygen in the air to form a complex chrome-oxide surface layer that is invisible but strong enough to prevent further oxygen from "staining" (rusting) the surface.
The film itself is extremely thin, about 130 Angstroms and one Angstrom is one millionth of a centimeter. This layer is described as passive (does not react or influence other materials), tenacious (clings to the layer of steel and is not transferred elsewhere) and self-renewing (if damaged, more chromium from the steel will be exposed to the air and form more chromium oxide).
This means that over a period of years a stainless steel knife can literally be worn away by daily use and will still remain stainless. Higher levels of chromium and the addition of other alloying elements such as nickel and molybdenum enhance this surface layer and improve the corrosion resistance of the stainless material. Chromium is always the deciding factor, although other elements, particularly nickel and molybdenum, are added to improve corrosion resistance.
Q. Is stainless steel magnetic?
A. There are several "types" of stainless steel. The 300 series (which contains nickel) is NOT magnetic. The 400 series (which just contains chromium and no nickel) ARE magnetic.
Q. What is the difference between 316 and 304 stainless steel?
A. 304 contains 18% chromium and 8% nickel. 316 contains 16% chromium, 10% nickel and 2% molybdenum. The "moly" is added to help resist corrosion to chlorides (like sea water and de-icing salts.
Q. Can stainless steel be welded?
A. YES. Stainless steel is easily welded, but the welding procedure is different than that used with carbon steel. The "filler" rod or electrode must be stainless steel.
Q. What temperatures can stainless steel withstand?
A. Stainless steel has excellent properties at both extremes of the temperature scale. Some stainless steel can be used down to liquid nitrogen temperatures and some up to about 1800° F.
Q. Does stainless steel rust?
A. Stainless does not "rust" as you think of regular steel rusting with a red oxide on the surface that flakes off. Corrosion is generally caused by contaminants settling on the surface of the stainless steel.
Q. Do you sell stainless steel and aluminium sheet?
A. YES. We have Aluminium; sheet, perforated sheet, propeller plate and treadplate sheet available as well as stainless steel sheet, perforated sheet and treadplate.
Q. Will stainless and aluminium corrode when in contact with each other?
A. Yes, two different metals will set up a red/ox reaction when they are wet, especially when salt is present. The metal with the lower oxidation potential will corrode, in this case the aluminium.
Q. What is the difference between ferrous and non-ferrous metals?
A. Ferrous Metals mostly contain Iron. They have small amounts of other metals or elements added, to give the required properties. Ferrous Metals are magnetic and give little resistance to corrosion.
Non-ferrous metals are specified for structural applications requiring reduced weight, higher strength, nonmagnetic properties, higher melting points, or resistance to chemical and atmospheric corrosion. They are also specified for electrical and electronic applications.
Q. Is stainless steel ferrous or non-ferrous metal?
A. Stainless steel is a ferrous metal as it contains iron.
Q. Is aluminium a ferrous or non-ferrous metal?
A. Aluminium is a non-ferrous metal as it does not contain iron.