What are the most used metals, and how much of them were used in 2018?
Steel: 1,808 million metric tonnes
Alumium: 21.9 million metric tonnes
copper: 14.9 million metric tonnes
gold: 2,600 metric tonnes
When was the first usage of cast iron during the structural revolution?
1779 - Iron bridge, coalbrookdale
What was the first major bridge built with wrought steel?
Forth Railbridge, scotland, 1890
What kind of bonding is present in metals?
What are the properties of metallic bonds
Free to move electrons make them malleable and good conductors, usually have high melting and boiling points
What kind of metals are most engineering metals?
What do FCC, HCP, BCC dstand for
FCC: Face centered cubic
HCP: hexagonal close packed
BCC: body centered cubic
What metals have an FCC structure?
Aluminium, copper, gold. lead, nickel, platinum, silver
What metals have a BCC structure?
Chromium, Iron (alpha), Molbdenum
What metalls have an HCP structure?
What type of imperfections are found in the chrystal structure?
- Substitutional Atoms (solutes)
- Interstital atoms (solutes)
- Grain boundaries
What is the definition of a grain boundary?
The interface between adjacent chrystalline regions that have different orientation
What is the definition of a dislocation?
An irregularity within a crystal strucutre that contains an abrupt change in the arrangmement of atoms
What is the difference between interstital and substitutional atoms?
interstital allow for the same number of metal atoms and is nessled into the microstructure,
Substiutional replace one of the metal atoms in the chrystal
What failure are grain boundaries resposible for?