Alloys_and_Heat_Treatment

Alloys_and_Heat_Treatment - MEGR 2180 Alloys and Heat...

Info iconThis preview shows pages 1–17. Sign up to view the full content.

View Full Document Right Arrow Icon
MEGR 2180 lloys and Heat Treatment Alloys and Heat Treatment
Background image of page 1

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

View Full DocumentRight Arrow Icon
MEGR 2180 Behavior and Manufacturing Properties of Materials Mechanical Physical and Property Structure of Properties Chemical Properties Modification Materials Atomic Bonds Crystalline morphous Strength Ductility lasticity Density Melting Point pecific Heat Alloying Heat Treatment recipitation hardening p Polymer Chains Elasticity Hardness Fatigue Creep Toughness Specific Heat Thermal Conductivity Thermal Expansion Electrical Conductivity Oxidation Precipitation hardening Annealing Tempering Surface treatment Reinforcements Fracture Corrosion Composites Laminations Fillers
Background image of page 2
MEGR 2180 ALLOYING • The mixing of metals and semi-metals in the olten state is called alloying molten state is called alloying • An alloy is composed of two or more chemical elements, at least one of which is a metal • Alloying is performed to improve the physical roperties of a metal properties of a 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
MEGR 2180 hase Diagrams Phase Diagrams
Background image of page 4
MEGR 2180 etal Solidification Metal Solidification • Phase Diagrams for pure metals are simpler than those for metal alloys y – Compositions don’t change reezing occurs at a Freezing occurs at a single temperature • Example – Cooling of a pure metal
Background image of page 5

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

View Full DocumentRight Arrow Icon
MEGR 2180 hase Diagrams Phase Diagrams hase Diagrams show the relationship among Phase Diagrams show the relationship among temperature, composition, and phase Alloys are described by stating the components and concentrations in weight or atom %
Background image of page 6
MEGR 2180 Phase Diagrams Important Examples • The Nickel-Copper Phase Diagram with solidus and liquidus curves • The Lead-Tin phase diagram with a well efined Eutectic point defined Eutectic point • The Iron-Carbon system because of the portance of steel is one of the most importance of steel is one of the most important phase diagrams
Background image of page 7

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

View Full DocumentRight Arrow Icon
MEGR 2180 opper Nickel Phase Diagram Copper Nickel Phase Diagram opper Nickel Micrograph Copper Nickel Micrograph
Background image of page 8
MEGR 2180 hase Diagrams Phase Diagrams Important Examples • The Lead-Tin phase diagram with a well defined Eutectic point • In another type of phase diagram, the two components are soluble in the liquid phase but not soluble in the solid phase • Eutectic point is the particular composition which has the lowest melting point
Background image of page 9

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

View Full DocumentRight Arrow Icon
MEGR 2180 LEAD-TIN PHASE DIAGRAM
Background image of page 10
MEGR 2180
Background image of page 11

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

View Full DocumentRight Arrow Icon
MEGR 2180 Reading the Phase Diagram • Find the Constitution point given that T = 250°C Composition wt % Pb = 80 • Draw a horizontal line across from Temp – Tie Line • Draw a vertical line from composition
Background image of page 12
MEGR 2180 Inverse Lever Law
Background image of page 13

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

View Full DocumentRight Arrow Icon
MEGR 2180 4 0 % 56 . 69 100 64 87 64 80 = = = x l a Solid % 4 . 30 100 4 7 80 87 = = = x b Liquid 64 87 l
Background image of page 14
MEGR 2180 Phase Diagrams Important Examples • The Iron-Carbon system because of the importance of steel is one of the most important phase diagrams • Steel and Cast Iron are represented by e on arbon hase diagram the Iron-Carbon phase diagram
Background image of page 15

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

View Full DocumentRight Arrow Icon
MEGR 2180 Liquid γ + Liquid L + Fe 3 C 2.14 4.20 B D γ (Austenite) Eutectic z γ + cementite (Fe 3 C) 0.022 0.8 Eutectoid H cementite (Fe ) 723°C α (Ferrite) 70 C Cementite (Fe 3 C) 0.25 1.2 α + cementite (Fe 3 C) 6.70 Cast Iron Steel
Background image of page 16
Image of page 17
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 10/01/2009 for the course MEGR 2144 taught by Professor Sharpe during the Fall '08 term at UNC Charlotte.

Page1 / 53

Alloys_and_Heat_Treatment - MEGR 2180 Alloys and Heat...

This preview shows document pages 1 - 17. Sign up to view the full document.

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