Metals Flashcards
What is a non ferrous metal?
Metals that do not contain iron(ferrite).
What is a ferrous metal?
Metals that contain iron(ferrite) and carbon.
What are the benefits of alloying?
Changes melting point
Changes the colour
Increases strength,hardness and ductility
Enhances resistance to corrosion and oxidation
Changes electrical/thermal properties
Improves flow properties
What is a ferrous alloy?
A mixture of two or more metals where at least one of which contains iron (ferrite) and carbon.
What is a non ferrous alloy?
A mixture of two or more metals where none of which contains iron (ferrite)
Name some ferrous metal?
Cast irons
Mild steel
Medium carbon steel
High carbon steel
Name some non ferrous metals?
Aluminium Copper Lead Tin Zinc
What is the advantage and disadvantage of sand casting?
Advantage - complex 3D shapes can be produced
Cores can be used to produce hollow sections
Appropriate for small runs
Automated processes are suitable for longer production runs
Disadvantages-poor surface finis
some machining will be necessary
Not as accurate as die or investment casting
Low rate of output so only suitable for small production runs
Name a non ferrous metal and it’s common use?
Aluminium-kitchenware products such as saucepan excellent conductor of electricity
Copper-electrical contacts,pipe work,jewellery high melting point
Gold-jewellery
Lead-adjoining brickwork very durable
Name some alloying steels?
Stainless Steel-alloyed with chrimium nickel,magnesium making it tough and wear resistant and corrosion resistant.
What is hardening?
Hardening of steels is carried out by heating the metal to cherry red followed by rapid cooling.
What is annealing?
Process of heating a metal that has been work hardened.Soaking the metal at an appropriate annealing temperature allows the crystals to reshape so relieving internal stresses that causes work hardening.
