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Most metal borides are hard; [41] however, a few stand out among them for their particularly high hardnesses (for example, WB 4, [42] [43] RuB 2, OsB 2 and ReB 2). These metal borides are still metals and not semiconductors or insulators (as indicated by their high electronic density of states at the Fermi Level ); however, the additional ...
Uranium and osmium were early successful catalysts in the Haber process, the nitrogen fixation reaction of nitrogen and hydrogen to produce ammonia, giving enough yield to make the process economically successful. At the time, a group at BASF led by Carl Bosch bought most of the world's supply of osmium to use as a catalyst. Shortly thereafter ...
The strength and high-temperature stability of refractory metals make them suitable for hot metalworking applications and for vacuum furnace technology. Many special applications exploit these properties: for example, tungsten lamp filaments operate at temperatures up to 3073 K, and molybdenum furnace windings withstand 2273 K.
This is a list of named alloys grouped alphabetically by the metal with the highest percentage. Within these headings, the alloys are also grouped alphabetically. Within these headings, the alloys are also grouped alphabetically.
4Cr14MoV, EN 1.4117 / DIN X38CrMoV15, good enough to make kitchen knives. 5Cr15MoV, some knives manufacturers define as 5Cr13MoV, the hardness could be 55–57 HRC. It's widely used to make kitchen knives, high-end scissors, folding knives, hunting knives, etc. It is equivalent to 1.4116 and German 4116 steel in composition.
As in the cases of other refractory metals, the hardest known compounds of tantalum are nitrides and carbides. Tantalum carbide, TaC, like the more commonly used tungsten carbide, is a hard ceramic that is used in cutting tools. Tantalum(III) nitride is used as a thin film insulator in some microelectronic fabrication processes. [38]
One tool to make this measurement is the sclerometer. Another tool used to make these tests is the pocket hardness tester. This tool consists of a scale arm with graduated markings attached to a four-wheeled carriage. A scratch tool with a sharp rim is mounted at a predetermined angle to the testing surface.