Steel Grades Guide

Steel is graded as a method of classification (steel grades). It is commonly categorised into these four groups – Carbon, Alloy, Stainless, and Tool.

  • Carbon Steels only contain trace amounts of elements besides carbon and iron. This group is the most common, accounting for 90% of steel production. Carbon Steel is divided into three subcategories: Low Carbon Steels/Mild Steels (up to 0.3% carbon), Medium Carbon Steels (0.3–0.6% carbon), and High Carbon Steels (more than 0.6% carbon).
  • Alloy Steels contain alloying elements such as nickel, copper, chromium, and aluminum. These additional elements are used to influence the metal’s strength, ductility, corrosion resistance, and machinability.
  • Stainless Steels are valued for their high corrosion resistance. These steels are commonly used in medical equipment, piping, cutting tools, and food processing equipment.
  • Tool Steels make excellent cutting and drilling equipment as they contain tungsten, molybdenum, cobalt, and vanadium to increase heat resistance and durability.
TYPE: CARBON STEEL
Grade Material Properties Common Applications
Carbon Steel
  • very high strength
  • extreme hardness
  • extreme resistance to wear
  • moderate ductility – a measure of a material’s ability to tolerate being deformed without actually breaking
  • Low-carbon steel – Low carbon steels are often used in automobile body components, structural shapes (I-beams, channel and angle iron), pipes, construction and bridge components, and food cans.
  • Medium-carbon steel – As a result of their high strength, resistance to wear and toughness, medium-carbon steels are often used for railway tracks, train wheels, crankshafts, and gears and machinery parts requiring this combination of properties.
  • High-carbon steel – Due to their high wear-resistance and hardness, high-carbon steels are used in cutting tools, springs high strength wire and dies.
TYPE: ALLOY STEEL – HASTELLOY STEEL
Grade Material Properties Common Applications
Hastelloy Steel
  • outstanding corrosion resistance
  • high-temperature strength
  • exceptional stress resistance

Hastelloy steel is suited to many industrial applications such as:

  • Heat Exchangers.
  • Columns
  • Condensors
  • Reactors
  • Pressure Vessels.
  • Piping Systems.
  • Spargers
TYPE: ALLOY STEEL – ICONEL STEEL
Grade Material Properties Common Applications
Iconel steel
  • high corrosion resistance
  • oxidation resistance
  • strength at high temperatures
  • creep resistance
  • high tensile strength
  • Aerospace and jet engines.
  • Oil and gas extraction.
  • Pollution control and waste processing.
  • Automotive Industry
  • Marine industry – saltwater applications
  • Heat treatment applications
  • Rapid temperature change applications – where temperatures may vary between near-cryogenic lows and heat treatment highs.
TYPE: ALLOY STEEL – MONEL STEEL
Grade Material Properties Common Applications
Monel Steel
  • resistant to corrosion and acids
  • Extreme temperature strength
  • marine engineering
  • chemical and hydrocarbon processing equipment
  • valves
  • pumps
  • shafts
  • fittings
  • fasteners
  • heat exchangers.
TYPE: STAINLESS STEEL
Grade Material Properties Common Applications
Stainless steel
  • Corrosion-resistant.
  • High tensile strength.
  • Very durable.
  • Temperature resistant.
  • Easy formability and fabrication.
  • Low-maintenance (long-lasting)
  • Recyclable

The wide variety of stainless steels means that the metal can be used in literally thousands of applications. The following gives a flavour of the full range:

  • Domestic – cutlery, lights, watches, washing machine drums, razor blades
  • Architectural/Civil Engineering – cladding, handrails, door and window fittings, structural sections, reinforcement bar, lintels, masonry supports
  • Transport – exhaust systems, car grilles, road tankers, ship containers, ships chemical tankers, refuse vehicles
  • Chemical/Pharmaceutical – pressure vessels, process piping
  • Oil and Gas– platform accommodation, cable trays, subsea pipelines
  • Medical – Surgical instruments, surgical implants, MRI scanners
  • Food and Drink– Catering equipment, brewing, distilling, food processing
  • Water – Water and sewage treatment, water tubing, hot water tanks
  • General – springs, fasteners (bolts, nuts and washers), wire
TYPE:304 STAINLESS STEEL
Grade Material Properties Common Applications
304 Stainless Steel
  • High Tensile Strength
  • Tough / Durable
  • Corrosion-resistant
  • High-Temperature Applications
  • Non-Magnetic
  • Easy to weld
  • Durable welds
  • Easy formability and fabrication.

Due to its immense versatility, 304 can be used across a wide variety of industrial applications

  • Appliances such as refrigerators and dishwashers.
  • Commercial Brewery, dairy, food and pharmaceutical production equipment
  • Springs, nuts, bolts and screws
  • Pressure Vessels
  • Piping
  • Heat exchangers.
  • Structures in environments that would corrode standard carbon steel.
TYPE:304L STAINLESS STEEL
Grade Material Properties Common Applications
304L Stainless Steel
  • Lower Carbon Content the 304 SS
  • Slightly lower Tensile strength than 304
  • Slightly lower Yield strength than 304
  • Weld joints less susceptible to corrosion than 304
  • Inherently tough
  • Corrosion-resistant
  • High-Temperature Applications
  • Non-Magnetic
  • Easy to weld
  • Durable welds
  • Easy formability and fabrication.

Due to its immense versatility, 304L can be used across a wide variety of industrial applications, especially in high-corrosion environments.

  • Aerospace and automotive structures
  • Architectural paneling, molding, trim and other details
  • Braces
  • Chemical containers to be used for transport
  • Cooking tools (such as pots and pans)
  • Construction material for buildings
  • Dyeing
  • Food processing equipment (such as wine, beer brewing, and milk)
  • Heat exchangers
  • Kitchen equipment (such as sinks or appliances)
  • Marine environment equipment (such as nuts, screws or bolts)
  • Railing and trim
  • Springs
  • Threaded fasteners
  • Welded or woven water filtration screens
TYPE:316 STAINLESS STEEL
Grade Material Properties Common Applications
316 Stainless Steel
  • Higher Corrosion resistance the 304 SS
  • Increased resistance the pitting and crevice corrosion
  • Inherently tough
  • High-Temperature Applications
  • Non-Magnetic
  • Easy to weld
  • Durable welds
  • Easy formability and fabrication.

The most familiar uses of type 316 stainless steel are:

  • construction of exhaust manifolds
  • furnace parts
  • heat exchangers
  • jet engine parts
  • evaporators
  • chemical processing equipment
  • pharmaceutical and photographic equipment
  • valve and pump parts
  • tanks
  • pulp, paper, and textile processing equipment
  • Equipment with parts that are exposed to marine environments.
TYPE:316L STAINLESS STEEL
Grade Material Properties Common Applications
316L Stainless Steel
  • Corrosion-resistant.
  • Suited to High-Temperature Applications
  • higher creep, stress-to-rupture and tensile strength at elevated temperatures.
  • excellent strength and toughness at cryogenic temperatures
  • Chemical and Petrochemical Processing — pressure vessels, tanks, heat exchangers, piping systems, flanges, fittings, valves and pumps
  • Food and Beverage Processing
  • Marine
  • Medical
  • Petroleum Refining
  • Pharmaceutical Processing
  • Power Generation — nuclear
  • Pulp and Paper
  • Textiles
  • Water Treatment
TYPE:316H STAINLESS STEEL
Grade Material Properties Common Applications
316H Stainless Steel
  • Corrosion-resistant.
  • Suited to High-Temperature Applications
  • greater tensile and yield strength.
  • excellent toughness, even down to cryogenic temperatures.
  • Greater short and long term creep strength
  • Chemical and Petrochemical Processing – pressure vessels, tanks, heat exchangers, boilers, piping systems, flanges, fittings, valves, and pumps
  • Food and Beverage Processing
  • Marine
  • Medical
  • Petroleum Refining
  • Pharmaceutical Processing
  • Power Generation — nuclear
  • Pulp and Paper
  • Textiles
  • Water Treatment
TYPE: DUPLEX STAINLESS STEEL
Grade Material Properties Common Applications
Duplex Stainless Steel
  • Excellent corrosion resistance
  • Increased resistance to chloride attack
  • Good resistance to stress corrosion cracking
  • Tensile and yield strength higher than austenitic or ferritic grades
  • Good weldability
  • Good formability

The extensive benefits of Duplex Stainless Steel mean that it can be used in many different are used in:

  • Chemical processing, transport and storage
  • Pipes for production and transportation of oil and gas
  • Oil and gas exploration and offshore rigs
  • Oil and gas refining
  • Marine environments
  • Pollution control equipment
  • Pulp & paper manufacturing
  • Chemical process plant
  • Structural and mechanical components
  • Heat exchangers
  • Cooling pipes
TYPE:SUPER DUPLEX STAINLESS STEEL
Grade Material Properties Common Applications
Super Duplex Stainless Steel
  • High strength
  • High corrosion resistance.
  • High resistance to stress corrosion cracking, corrosion fatigue and erosion
  • High thermal conductivity
  • Low coefficient of thermal expansion
  • Good weldability
  • Good formability

Super duplex is particularly suited for the following applications:

  • Heat exchangers, tubes and pipes for processing gas and oil
  • Pipes in processes containing chlorides
  • Cargo tanks – piping for chemical tankers
  • Shafts, rotors and hydraulic lines

The high strength and low corrosion of super duplex means it is widely used in the following industries

  • Petrochemical
  • Water desalinisation
  • Chemical processing
  • Marine and shipping
  • Oil and Gas production
OTHER MATERIALS: ALUMINIUM
Grade Material Properties Common Applications
Aluminum
  • Lightweight
  • Strong
  • Resistant to corrosion
  • Durable
  • Ductile
  • Malleable
  • Conductive
  • Odorless
  • Easily Recyclable

The most common uses of aluminum include:

  • Transportation
  • Construction
  • Electrical
  • Consumer Goods
OTHER MATERIALS: DUCTILE IRON
Grade Material Properties Common Applications
Ductile Iron
  • High Hardness
  • High Toughness
  • Ductile
  • Elasticity
  • Malleability
  • Tensile strength
  • Fatigue strength

Some of the best uses for the durable, flexible, and cost-effective ductile are included:

  • Valves (especially high-pressure valves)
  • Pipe and pipe fittings – Water and sewer lines
  • Connecting rods (like in engines)
  • Crankshafts
  • Cylinders
  • Hydrostatic Barrels
  • Military uses
  • Automotive components
  • Gearboxes, Yokes for power transmission
  • Pump housings
  • Large Machines, Machine Tooling
  • Wheels and Axles
  • Agricultural tractors
  • Oil well pumps

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