Recommended
More Related Content
Similar to STEEL.pdf
Similar to STEEL.pdf (20)
Recently uploaded
Recently uploaded (20)
STEEL.pdf
- 1. GOVERNMENT ENGINEERING COLLEGE GANDHINAGAR Vyomee Bagiya 220130141052 Heer Gokani 220130141015 Mahetab Ghanchi 220130141013 Nirali Chauhan 220130141009 STEEL
- 2. TABLE OF CONTENTS Introduction Classification of steel based on carbon content Physical properties Factors affecting physical properties 01 02 03 04
- 3. TABLE OF CONTENTS Market forms of steel Uses 05 06
- 4. Introduction Steel is comprised mostly of Iron and has some carbon mixed in different proportions to create different kinds of steel. While carbon is the main property changing factor, other alloying metals are also added such as sulphur, phosphorus, manganese, silicon, etc.
- 6. MILD STEEL ● 0.15-0.25% Carbon ● 0.05% Sulphur ● 0.055% Phosphorus Composition ● Very ductile, malleable, elastic. ● Easily forged, welded or riveted. ● Strong in compression, tension and shear. Properties ● Manufacturing of rolled structural sections. ● Bars for reinforcements of concrete and sheets for roof coverings. ● For making equipments, tools and machine parts. Uses
- 7. MEDIUM CARBON STEEL ● 0.25-0.70% Carbon ● 0.9% Manganese ● 0.05% Sulphur ● 0.04% Phosphorus Composition ● Granular structure. ● Easy to harden and temper, difficult to forge and weld. ● Stronger in compression than tension and shear. ● Absorbs shocks and vibrations. Properties ● Making tools like drills, files, chisels. ● Machines needing durable and shock absorbing parts. ● Railway wheels, and tracks, gears, crankshafts. Uses
- 8. HIGH CARBON STEEL ● 0.70-1.5% Carbon ● 0.6% Manganese ● 0.2% Silicon ● 0.05% Sulphur ● 0.05% Phosphorus Composition ● Tougher and more elastic. ● Increased tensile strength, high hardness. ● Brittle and less ductile. ● Resists corrosion. Properties ● For reinforcing pre-stressed concrete structures. ● In tools and die steels. Uses
- 9. OTHERS DEAD MILD STEEL (<0.15% C) ● Most abundant grade of steel, least expensive. ● Good weldability. ● Unresponsive to heat treatment, need cold working to improve strength. 01 02 CAST STEEL/CARBON TOOL STEEL (>1.5%C) ● Crystalline structure, brittle. ● Easy to cast into any shape. ● Does not rust. ● Easy to recycle.
- 10. PHYSICAL PROPERTIES Lowest of all building materials available. Strength to weight ratio Dimensional stability Ductility Conductance Recyclable Remains unchanged for many years or after subjected to extreme environmental conditions. Can be easily molded into any shape. Good conductor of electricity and heat. Efficient to recycle without losing its properties.
- 11. PHYSICAL PROPERTIES Good durability for a building material. Durability Resistance to corrosion Quality Does not corrode easily on exposure to moisture like its constituents iron and carbon. Higher carbon content gives more strength and high quality steel with less carbon is more ductile. Now it is manufactured to ensure good strength and ductility by rapid cooling.
- 13. Factors affecting physical properties Tensile strength of steel increases with carbon content up to 0.8% and decreases after that. Ductility, hardness and strength also increases with carbon content. Carbon Content 01 02 Presence of Impurities If sulphur content in steel is between 0.02-0.10%, it has no appreciable effect on ductility and strength of steel. Excess sulphur will decrease ductility and strength.
- 14. 03 The phosphorus content in steel should be below 0.12%. Excess phosphorus reduces ductility, strength and shock resistance. If silicon content is less than 0.20%, it has no effect on physical properties. If it is increased to 0.30-0.40$, elasticity and strength increases without reduction in ductility. Manganese helps to improve strength of mild steel. Desirable content is 0.30-1.0%. If it exceeds 1.50%, steel becomes very brittle. Heat Treatment Processes Most steel are subjected to 3 basic processes: annealing, quenching and tempering.
- 15. Steel is heated beyond its critical temperature for the annealing process.During this phase, the grain quality of the steel changes. Heat treated steel must be tempered before it can be used as a commercial material. Tempering is also heating steel, but this time below the critical temperature. Tempering steel is a way to make hardened steel less brittle and change its durability to suit your needs. Quenching is the industry term for rapidly cooling hot steel to make it hard again. Depending on the project, hot and malleable steel will be dipped in either water or oil to cool. This brings the steel back to a solid state and often leaves it brittle.
- 16. Market Forms of Steel
- 17. Market Forms of Steel