MCE 230_F10_ lec_13 - types of atoms is less than +- 15%....

Info iconThis preview shows pages 1–6. Sign up to view the full content.

View Full Document Right Arrow Icon
MCE 230 – Materials Science Fall 2010 Lecture - 13
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Imperfections in Solids
Background image of page 2
Impurities in Solids Pure material consists of only one type of atoms It is very difficult to produce 100% pure material crystals solid contains vacancies, and it is not possible to have a vacancy free material Impurities are atoms which are different than the original material atoms Alloying: intentionally adding impurity atoms to enhance certain properties of the metal
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Solid Solutions When solute atoms are added to solvent “host” atoms, and the crystal structure is maintained. Factors affecting the formation of solid solutions: 1. Atomic size factor: difference between atomic radii of the two
Background image of page 4
Background image of page 5

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Background image of page 6
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: types of atoms is less than +- 15%. Otherwise there will be lattice distortions and new phase will form. 2. Crystal Structure: both atom types must have the same crystal structure 3. Electronegativity: the more electropositive one of them and the more electronegative the other one, the greater the chance to form metallic compound rather than solid solution 4. Valences: other factors being equal, a metal will have more tendency to dissolve another metal with higher valency Composition (concentration)  Weight percentage ( where m is the weight or mass of element)  Atom percentage (where m’ is mass (grams) and A is the atomic weight) Composition Conversions...
View Full Document

This note was uploaded on 12/05/2010 for the course MECHANICAL mce 230 taught by Professor Bassildrass during the Fall '10 term at American University of Sharjah.

Page1 / 6

MCE 230_F10_ lec_13 - types of atoms is less than +- 15%....

This preview shows document pages 1 - 6. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online