Metallurgy of Alloys in Dentistry

<p>Homogenization anneal (A)</p> Signup and view all the answers

<p>Reduced mechanical performance (C)</p> Signup and view all the answers

<p>Duration at the solidus temperature (C)</p> Signup and view all the answers

<p>They diffuse to reach equilibrium (B)</p> Signup and view all the answers

<p>The alloy's composition may remain non-homogeneous (C)</p> Signup and view all the answers

<p>Thermal stability (C)</p> Signup and view all the answers

<p>Solid and below the solidus temperature (D)</p> Signup and view all the answers

<p>The phases present at varying temperatures and compositions (B)</p> Signup and view all the answers

<p>780°C (A)</p> Signup and view all the answers

<p>Eutectoid composition (C)</p> Signup and view all the answers

<p>Coarse dendritic structure leading to segregation (B)</p> Signup and view all the answers

<p>They consider time as an essential factor for phase equilibrium (C)</p> Signup and view all the answers

<p>Copper precipitates out as a new stable phase (B)</p> Signup and view all the answers

<p>Eutectoid involves only solid phases, while eutectic includes liquid phases (B)</p> Signup and view all the answers

<p>The phase with the highest melting point (D)</p> Signup and view all the answers

<p>It often prevents the formation of equilibrium structures (A)</p> Signup and view all the answers

<p>A copper-rich solid solution (B)</p> Signup and view all the answers

<p>It separates the solid phase from the liquid and solid mixture. (A)</p> Signup and view all the answers

<p>The latent heat of fusion is being released. (B)</p> Signup and view all the answers

<p>The temperature range for phase transitions. (C)</p> Signup and view all the answers

<p>The existence of two distinct solid phases in a mixture. (D)</p> Signup and view all the answers

<p>It results in a constant temperature during solidification. (D)</p> Signup and view all the answers

<p>Using cooling curves of various compositions. (C)</p> Signup and view all the answers

<p>Phase transitions occur over a wider temperature range. (D)</p> Signup and view all the answers

<p>The end of the liquid-solid phase region. (B)</p> Signup and view all the answers

<p>The temperature begins to decrease. (B)</p> Signup and view all the answers

<p>It alters the positions of the liquidus and solidus lines. (B)</p> Signup and view all the answers

<p>Atoms must have the same crystal structure and be of similar valency (B)</p> Signup and view all the answers

<p>Gold and copper (C)</p> Signup and view all the answers

<p>Less than 60% of the diameter (D)</p> Signup and view all the answers

<p>Atoms must be the same size (B)</p> Signup and view all the answers

<p>Formed by a specific combination of metals in a new phase (D)</p> Signup and view all the answers

<p>They graphically represent phases and compositions at various temperatures (A)</p> Signup and view all the answers

<p>Gold and copper have atomic diameters that are very similar (A)</p> Signup and view all the answers

<p>The availability of interstitial spaces in the lattice (A)</p> Signup and view all the answers

<p>Interstitial solutions involve solute atoms occupying voids between solvent atoms (A)</p> Signup and view all the answers

A process that eliminates or reduces compositional segregation in alloys by heating them just below the solidus temperature.

The temperature at which a solid begins to melt and becomes a liquid.

The process of heating and cooling an alloy to improve its properties.

A mixture of two or more metals.

The movement of atoms within a material.

The state of balance where atoms are evenly distributed.

The property of a material that resists deformation under stress.

A substance that cannot be decomposed into simpler substances by chemical means.

The process of preparing an alloy for use.

The uneven distribution of different components in an alloy.

The line on a phase diagram that separates the liquid phase from the liquid and solid mixture.

The line on a phase diagram that separates the solid phase from the liquid and solid mixture.

The energy released or absorbed during a change of state, specifically when a substance solidifies at a constant temperature.

The phenomenon where components of a material are not fully soluble in each other, resulting in two solid phases.

A graphical representation that shows the phases of a substance as a function of temperature and composition.

The process of changing from a liquid to a solid state.

The constant temperature during solidification of a pure metal due to the release of latent heat.

The point on a cooling curve for an alloy where the liquid phase starts to solidify.

The point on a cooling curve for an alloy where the last bit of liquid solidifies.

A type of solid solution where solute atoms occupy spaces between solvent atoms in the crystal lattice. The solute atom must be much smaller than the solvent atom, and the lattice must have space to accommodate the smaller atoms.

A type of solid solution where solute atoms directly substitute solvent atoms in the crystal lattice. This requires similar valencies, crystal structures, and atomic sizes within 15% of each other.

A mixture of elements at the atomic level. They can be substitutional, where solute atoms replace solvent atoms, or interstitial, where solute atoms fit in spaces between solvent atoms.

A new phase formed when two or more metals combine in a specific composition. Examples include phases in dental amalgam alloys like Ag-Sn and Cu-Sn.

A type of phase diagram that shows the phases of a two-component alloy. These are simpler to understand than more complex diagrams.

The size of an atom, typically measured in Angstroms (Å).

The arrangement of atoms in a crystalline solid. Some common types include FCC (Face-Centered Cubic), BCC (Body-Centered Cubic), and HCP (Hexagonal Close-Packed).

The number of electrons an atom can gain or lose to participate in chemical bonding.

Similar characteristics between atoms, such as valency, crystal structure, and atomic size, which allow them to form substitutional solid solutions.

A graphical representation showing the different phases (solid, liquid, gas) of a material at different temperatures and compositions. It helps predict what phases will be present in an alloy at a given temperature and composition.

A phase diagram that shows the conditions where a material is in its most stable state. It assumes all phases have enough time to reach this stable state during solidification.

A phase diagram with two metal components, showing the solubility of each metal in the other at different temperatures.

A phase diagram that shows the relationship between temperature, composition, and phases in a solid solution. It's usually represented by a Greek letter like α, β, or γ.

It refers to the maximum amount of one element that can dissolve in another element at a given temperature.

The point on a phase diagram where three phases coexist. This is usually found at a specific temperature and composition.

The specific composition of a solid solution where it transforms into two different phases at a certain temperature. This is usually found at a specific composition.

A solid solution structure where the solid phase forms with a wide range of compositions. This happens when cooling rates are too fast for the alloy to reach equilibrium.

Branch-like structures that form during solidification of alloys. They occur due to rapid cooling and non-equilibrium conditions, leading to variations in composition.

A phase diagram that describes the equilibrium phases for a metal alloy system under ideal conditions. However, real-world circumstances rarely allow for complete equilibrium.