Stainless steels are in general grouped into
- martensitic stainless steels
- ferritic stainless steels
- austenitic stainless steels
- duplex (ferritic-austenitic) stainless steels
- precipitation-hardening stainless steels
Alloying metallic elements added during the making of the steel increase corrosion resistance, hardness, or strength. The metals used most commonly as alloying elements in stainless steel include chromium, nickel, and molybdenum.
Stainless steels are available in the form of
Stainless steels are a iron-based alloy containing at between 10.5% to 30% Cr. Stainless steel achieve its stainless characteristic through the formation of an invisible and adherent chromium-rich oxide surface film.
Other alloying elements added to improve the characteristics of the stainless steel include nickel, molybdenum, copper, titanium, aluminum, silicon, niobium, nitrogen, sulphur, and selenium.
Carbon is normally in amounts from 0.03% to more than 1.0% in some martensitic grades.
Selection of stainless steels are in general based on
- corrosion resistance
- fabrication characteristics
- mechanical properties for specific temperature ranges
- product cost
Since stainless steel resists corrosion, maintains its strength at high temperatures, and is easily maintained, it is widely used in items such as automotive and food processing products, as well as medical and health equipment. The most common US grades of stainless steel are:
The most commonly specified austenitic (chromium-nickel stainless class) stainless steel, accounting for more than half of the stainless steel produced in the world. This grade withstands ordinary corrosion in architecture, is durable in typical food processing environments, and resists most chemicals. Type 304 is available in virtually all product forms and finishes.
Austenitic (chromium-nickel stainless class) stainless steel containing 2%-3% molybdenum (whereas 304 has none). The inclusion of molybdenum gives 316 greater resistance to various forms of deterioration.
Ferritic (plain chromium stainless category) stainless steel suitable for high temperatures. This grade has the lowest chromium content of all stainless steels and thus is the least expensive.
The most widely used martensitic (plain chromium stainless class with exceptional strength) stainless steel, featuring the high level of strength conferred by the martensitics. It is a low-cost, heat-treatable grade suitable for non-severe corrosion applications.
The most widely used ferritic (plain chromium stainless category) stainless steel, offering general-purpose corrosion resistance, often in decorative applications.
Piping codes and standards - ASME, ANSI, ASTM, AGA, API, AWWA, BS, ISO, DIN and more..
Material properties of gases, fluids and solids - densities, specific heats, viscosities and more.
Hot and cold water service systems - design properties, capacities, sizing and more.
Thermal diffusivity, specific heat capacity, density and thermal conductivity of stainless steel AISI 310 vs. temperature.
Pipe sizes, inside and outside diameters, wall thickness, schedules, moment of inertia, transverse area, weight of pipe filled with water - U.S. Customary Units.
Theoretic bursting and collapsing pressures for stainless steel pipes ASTM A312.
ASME/ANSI B16.5-1996 Pipe Flanges and Flanged Fittings - Class 150 Flanges - outside and inside diameters, bolt circles, numbers and diameters of bolts.
Copper, Ductile Iron, Carbon Steel, Stainless Steel and Aluminum Piping Materials - Temperature Expansion
Thermal expansion of typical piping materials.
Thermal expansion of PVC, CPVC, Carbon and Stainless Steel and Fiberglass pipes.
Comparing international stainless steel standards from America (US), France, Germany, Italy, Japan, Russia, Spain, Sweden, England (UK) and the European Union.
Allowable pressure for standard seamless A312-TP316/316L stainless steel pipes - temperatures 100oF to 750oF.
American - US - vs. European - German, British (UK) and Swedish - stainless steel pipe standards.
Dimensions, wall thickness and weights of stainless steel pipes according to ASME B36.19 Stainless Steel Pipes.
Dimensions of stainless steel weld fittings according ANSI/ASME B36.19.
Corrosion resistanse of AISI stainless steels in various environments.
Magnetic, spark, hardness and acid identification tests for austenitic, martensitic and ferritic stainless steels.
The tempering process of hardening steel.
The Unified Numbering System - UNS - used for metals and alloys.