Hume-Rothery rules

Hume-Rothery rules

Hume-Rothery rules

The Hume-Rothery rules are a set of basic rules describing the conditions under which an element could dissolve in a metal, forming a solid solution. There are two sets of rules, one which refers to substitutional solid solutions, and another which refers to interstitial solid solutions.


=Substitutional Solid Solution RuleFor substitutional solid solutions, the Hume-Rothery rules are::1. The atomic radii of the solute and solvent atoms must differ by no more than 15%:

:: % mbox{ difference} = left ( frac{(r_{solute} - r_{solvent})}{r_{solvent ight ) * 100 le 15%

:2. The crystal structures of solute and solvent must match.

:3. Maximum solubility occurs when the solvent and solute have the same valency. Metals with lower valency will tend to dissolve metals with higher valency.

:4. The solute and solvent should have similar electronegativity. If the electronegativity difference is too great, the metals will tend to form intermetallic compounds instead of solid solutions.


= Interstitial Solid Solution Rules =

For interstitial solid solutions, the Hume-Rothery rules are:

:1. Solute atoms must be smaller than the pores in the solvent lattice.

:2. The solute and solvent should have similar electronegativity. [ cite encyclopedia | title = Hume-Rothery Rules | encyclopedia = Van Nostrand's Scientific Encyclopedia | publisher = John Wiley & Sons, Inc. | date = 2002 ]

References

*cite web | last = Bhadeshia | first = H. K. D. H. | title = Solid Solutions: The Hume-Rothery Rules | url=http://www.msm.cam.ac.uk/phase-trans/2004/titanium/hume.rothery.html | accessdate = 2007-11-24


Wikimedia Foundation. 2010.

Игры ⚽ Поможем решить контрольную работу

Look at other dictionaries:

  • Hume-Rothery , William — (1899–1968) British metallurgist The son of a lawyer, Hume Rothery was born at Worcester Park in Surrey. He originally intended to pursue a military career and consequently entered the Royal Military Academy, Woolwich, on leaving school. An… …   Scientists

  • Règle de Hume-Rothery — Règles de Hume Rothery En chimie, les règles de Hume Rothery, du nom de William Hume Rothery qui les a énoncées la première fois, donnent les conditions de base pour obtenir un alliage homogène avec solubilité totale à l état solide (c est à dire …   Wikipédia en Français

  • Règles de Hume-Rothery — En chimie, les règles de Hume Rothery, du nom de William Hume Rothery qui les a énoncées la première fois, donnent les conditions de base pour obtenir un alliage homogène avec solubilité totale à l état solide (c est à dire une solution solide).… …   Wikipédia en Français

  • Reglas de Hume-Rothery — Saltar a navegación, búsqueda En las disoluciones sólidas aparecen ciertos defectos puntuales de dos tipos: sustitucionales e intersticiales. Las reglas de Hume Rothery establecen las condiciones necesarias que debe presentar una solución sólida… …   Wikipedia Español

  • Solid solution — Fig. 1 A binary phase diagram displaying solid solutions over the full range of relative concentrations. A solid solution is a solid state solution of one or more solutes in a solvent. Such a mixture is considered a solution rather than a… …   Wikipedia

  • Solid solution strengthening — is a type of alloying that can be used to improve the strength of a pure metal. The technique works by adding atoms of one element (the alloying element) to the crystalline lattice another element (the base metal). The alloying element diffuses… …   Wikipedia

  • Crystal structure — In mineralogy and crystallography, crystal structure is a unique arrangement of atoms or molecules in a crystalline liquid or solid. A crystal structure is composed of a pattern, a set of atoms arranged in a particular way, and a lattice… …   Wikipedia

  • quasicrystal — /kway zuy kris tl, kway suy , kwah see , zee /, n. a form of solid matter whose atoms are arranged like those of a crystal but assume patterns that do not exactly repeat themselves. [1985 90] * * * Introduction also called  quasi periodic crystal …   Universalium

  • X-ray crystallography — can locate every atom in a zeolite, an aluminosilicate with many important applications, such as water purification. X ray crystallography is a method of determining the arrangement of atoms within a crystal, in which a beam of X rays strikes a… …   Wikipedia

Share the article and excerpts

Direct link
… Do a right-click on the link above
and select “Copy Link”