Search results
Results from the WOW.Com Content Network
Osmium is a hard, brittle, blue-gray metal, and the densest stable element—about twice as dense as lead. The density of osmium is slightly greater than that of iridium ; the two are so similar (22.587 versus 22.562 g/cm 3 at 20 °C) that each was at one time considered to be the densest element.
Main page; Contents; Current events; Random article; About Wikipedia; Contact us
Osmium is a hard but brittle metal that remains lustrous even at high temperatures. It has a very low compressibility. Correspondingly, its bulk modulus is extremely high, reported between 395 and 462 GPa, which rivals that of diamond (443 GPa). The hardness of osmium is moderately high at 4 GPa.
The ductile failure model of Lynch [17] and Popovich [18] predicted that adsorption of the liquid metal leads to the weakening of atomic bonds and nucleation of dislocations, which move under stress, pile up and work harden the solid. Also, dissolution helps in the nucleation of voids which grow under stress and cause ductile failure.
Embrittlement is used to describe any phenomena where the environment compromises a stressed material's mechanical performance, such as temperature or environmental composition. This is oftentimes undesirable as brittle fracture occurs quicker and can much more easily propagate than ductile fracture, leading to complete failure of the equipment.
Osmium is a chemical element with the symbol Os and atomic number 76. It is a hard, brittle, blue-gray or blue-black transition metal in the platinum family and is the densest naturally occurring element, with a density of 22.59 g/cm 3 (slightly greater than that of iridium and twice that of lead ).
Get AOL Mail for FREE! Manage your email like never before with travel, photo & document views. Personalize your inbox with themes & tabs. You've Got Mail!
The dashed line is the traditional dividing line between metals and nonmetals. The symbols for the elements commonly recognized as metalloids are in italics. The status of elements 110 to 118 has not been confirmed, though elements 113-116 are sometimes considered post-transition metals.