STAINLESS STEEL PRODUCTS
Stainless steel is an alloy of Iron with a minimum of 10.5% Chromium. Chromium produces a thin layer of oxide on the surface of the steel known as the ‘passive layer’. This prevents any further corrosion of the surface. Increasing the amount of Chromium gives an increased resistance to corrosion.
Stainless steel also contains varying amounts of Carbon, Silicon and Manganese. Other elements such as Nickel and Molybdenum may be added to impart other useful properties such as enhanced formability and increased corrosion resistance.
PRECIPITATION HARDENING (PH)
These steels can achieve very high strength through precipitation hardening, which involves a heat treatment process and the addition of elements such as Copper, Niobium, and Aluminium to the steel.
The steel can be machined to quite intricate shapes requiring good tolerances before the final aging treatment as there is minimal distortion from the final treatment.
Corrosion resistance is comparable to standard austenitic steels like 1.4301 (304).
These steels are based on Chromium with small amounts of Carbon usually less than 0.10%.
They are chosen for their resistance to stress corrosion cracking.
These products are magnetic.
Their microstructure is derived from the addition of Nickel, Manganese and Nitrogen. This structure gives these steels their characteristic combination of weldability and formability. Corrosion resistance can be enhanced by adding Chromium, Molybdenum and Nitrogen. Standard austenitic steels are vulnerable to stress corrosion cracking. These product are non-magnetic.
These steels are based on Chromium but have higher Carbon levels up as high as 1%. Allowing them to be hardened and tempered much like carbon and low-alloy steels. They are used where high strength and moderate corrosion resistance is required. They have generally low weldability and formability. These products are magnetic.
These steels have a microstructure which is approximately 50% ferritic and 50% austenitic.This gives them a higher strength than either ferritic or austenitic steels and are resistant to stress corrosion cracking.
“Lean duplex” steels are formulated to have comparable corrosion resistance to standard austenitic steels but with enhanced strength and resistance to stress corrosion cracking.
“Superduplex” steels have enhanced strength and resistance to all forms of corrosion compared to standard austenitic steels.