-Also called low-carbon or soft-cast steel is the common type of steel used in construction.
-Carbon 0.1 - 0.3% and Iron 99.9.
Mild Steel Properties
- Steel is an alloy of iron and carbon; mild steel contains only a tiny proportion of carbon ( less than 0.25 percent), but can have other metals added, to create high-strength low alloy steel (HSLA)- copper, for example, improves corrosion resistance, nickel surface quality and nitrogen strength and weldability.
- Mild steel is annealed ( heated red- hot then cooled slowly) to improve workability and reduce its brittleness.
- Mild steel can also be galvanized with zinc for a waterproof finish.
- It can be welded, cut, rolled, folded or bent into shape and maintains stability.
- Mild steel does not promote fire spread, but structural steel should be encased or painted with flame proof paint.
- It has high strength in tension and compression, and retains impact resistance at low temperature.
Mild Steel Use and Maintenance
- Due to superior strength and weldability, mild steel is mainly used for structural elements such as trusses, beams, lintels and posts.
- Specialized items can be fabricated.
- Perforated or sheets are available for screen or panels and tubes can be used for table legs.
- Galvanized steel is used for outdoor furniture, planters and watering cans.
- Cor-ten is often chosen for sculptures because of its attractive color.
Stainless Steel
Properties
- Stainless steel are a group of alloy steels that contain iron, les than 1% carbon, 10% chromium or more and other alloys.
- Stainless steel is resistant to water and atmospheric corrosion.
- Certain grades even resist acids and chlorine.
- It has high strength in tension and compression, and is heat – and fire- resistant.
- It is also impact-resistant, even at low temperatures.
- It can be welded, cut, rolled, folded and bend into shapes (using specialized equipment) and will maintain stability.
- Stainless steel is an integral material, so requires no sealant or added surface protection.
Use and Maintenance
- Stainless steel does not deteriorate and requires no sealant or applied surface finish.
- Its regular, brushed look has a high-tech, modern feel.
- Its smooth surface is easy to wipe clean and perfect for areas requiring a high level of hygiene.
- It is used for indoor and outdoor products, including outdoor furniture, exterior light fixtures, household appliances and ironwork.
- Sheets can also be used as paneling or to line wet areas, and as structural or decorative elements in garden design.
- Carbon steels have low, medium or high carbon content, ranging from approximately 0.2-2%.
- Higher carbon content produces a harder, less ductile and more brittle material.
- Mild steel (plain carbon steel) is a term that covers a range of carbon steels Up to 0.25% carbon content.
- They are distinguished by ease of solid state forming and welding.
- Low carbon steels are relatively ductile, malleable and easy to shape.
- In contrast, high carbon steels are hard and as a consequence they are both resistant to abrasion and more brittle.
Use /Application
- Low carbon steel is used a great deal in construction, automotive metalwork and mill products such as sheet, strip, beams and sections.
- Medium carbon steel is used for crankshafts,chassis,springs, forging and pressure vessels.
- High carbon steel is used for springs, high strength wire and low cost cutting tools.
Low alloy Steel
Properties
- Low alloy steels are made up of iron, carbon and up to approximately 10% of other metals, such as nickel and chromium. The additional alloys are used to improve certain properties of the steel such as resistance to corrosion, formability and toughness
- Low alloy steels are also used in construction.
- The alloys in this particular grade of steel eliminate the need for protective coatings. The material develops a protective oxidized layer that prevents further corrosion of the metal
Tool Steel
- Tool steels are so called because they are used for cutting tools and dies.
- The carbon and alloy content make them hard, tough and resistant to abrasion even at high temperatures.
- Specific examples include high-speed steel (HSS) and mold steels.
- Steels with carbon content between approximately 0.3-0.7% are suitable for hardening by heat treatment.
- Normalized steel is heated to between 800°C and 900'C (1472-1652°F) and then slowly cooled, which allows the microstructure to develop into a strong formation.
- Quenched steel is cooled very rapidly in cold water and so is very hard and very brittle.
- Tempered steel is quenched and then heated up to 2000C (392°F) for an hour before cooling, which allows the carbon particles to diffuse and develop the steel's toughness and ductility.
Use /Application
- Tool steels are typically used in tools such as screwdrivers, hammers, and cutting tips and saw blades.
- They are also used to make dies for melt processing plastics and some metals.
Cast Iron
Properties
- Cast iron is made up of iron, carbon and small amounts of silicon.
- There are different types, including grey, white, ductile and malleable.
- They are differentiated by the formation of carbon in the iron matrix and alloying elements.
- Generally, cast iron has good dampening properties and machinability, is resistant to fatigue and corrosion and is difficult to weld due to the high carbon content.
Wrought Iron
- Almost 100% iron
Properties
-Wrought iron is a mixture of near-pure iron with up to 5 percent noncorrodible glass slags. -These form linear fibers in the metal, making it workable under high heat.
-It is not suitable for machining and is forged or handworked with hammer and anvil by a blacksmith.
-Wrought iron is not brittle, seldom breaks and is strong in tension and compression ( stronger than cast iron, which is shaped by being melted into a mold)
-Being handcrafted, it is expensive, but it is extremely long-lasting.
Wrought Iron Use and Maintenance
- Decorative finishing, accessories and security gates. It is perfect for outdoor furniture, and popular indoors chair, beds and door hardware
Copper
Properties
-This material has high capacity for conducting heat and electricity.
-Its resists atmospheric corrosion ( but will dissolve in nitric acid) and is nontoxic, malleable and easy to use.
-Copper will maintain stability when rolled, folded or bent into shapes, which is easily achieved with specialized equipment.
- It can be chemically treated to create a variety of finishes, such as bright or deep green or brown, or mottled or textured effects.
- Because of its softness, copper is not suitable as a structural material.
- It can be combined with numerous metals form alloys and does not burn or support combustion.
Use and Maintenance
-Copper pipes are extensively used in water and gas plumbing, and copper wiring in electric and electronic installations.
-As sheeting, copper is used for roofs-both for its functional weatherproofing quality and as a finishing material to highlight its natural beauty.
-It features in interior and exterior furniture, light fixtures, ironwork and ornamental crafts.
-It can also be used indoors in areas subject to heat, such as kitchen or fireplace hoods, counters and backsplashes, cookware and cutlery.
-It is suitable for wet applications too, including bathtubs, shower trays and basins, but use a sealant if you want to avoid tarnishing the pinkish red finish.
-It can be textured for a hammered or dimpled finish.
