Chapter 6 Flashcards
Define: Alloy
Metal composed of two or more elements, at least one of which is metallic (solid solutions and intermediate phases)
Define: Ferrous Metal
Metals based on iron.
Define: Solution
In which an alloy of one element is dissolved in another to form a single-phase structure.
Define: Substitutional vs. Interstitial
Substitutional: atoms of the solvent element are replaced in its unit cell by the dissolved element.
Interstitial: atoms of dissolving element fit into vacant spaces between base metal atoms in the lattice structure.
Define: Phase Diagram
Graphical means of representing the phases of metal alloy system as a function of composition and temperature.
Define: Segregation
When an alloy freezes, this occurs in the solid mass because of non-equilibrium conditions.
Define: Eutectic Alloy
Particular composition in an alloy system for which the solidus and liquidus are at the same temperature.
Define: Eutectoid Temperature
Melting Point of the Eutectic Composition
Define: Cast Iron
When the carbon content in the iron is between 2.1% and 5%
Define: Ferrite
Room temperature iron (alpha)
Define: Austenite
When ferrite reaches 912 C (gamma)
Define: Cementite
Fe3C ; intermediate phase in the iron-carbon alloy system.
Define: Steel
When carbon content is less than 2.1% to about .02%.
Define: Stainless Steel
Highly alloyed steels designed to provide high corrosion resistance. Principle alloying element in stainless steel is chromium.
Define: Free-machining Steel
Carbon steels formulated to improve machinability by alloying with elments such as sulfur, lead, tin, bismuth, and/or phosphorus. Help to lubricate the cutting operations, reduce friction, and break up chips for easier disposal.
