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This alloy is non-magnetic, easy to cast, and usually doesn’t require surface finishing. It has a low coefficient of friction, low melting point, good malleability, and high corrosion resistance.
On many periodic tables, a jagged black line (see figure below) along the right side of the table separates the metals from the nonmetals. The metals are to the left of the line (except for hydrogen, which is a nonmetal), the nonmetals are to the right of the line, and the elements immediately adjacent to the line are the metalloids.
Brass is most widely used in applications that are decorative and mechanical. Due to its unique properties, which include corrosion resistance, common uses for brass include applications that require low friction. These applications can include fittings (fasteners and connectors), tools, appliance parts, and ammunition components.
By the 8th–7th century BC Assyrian cuneiform tablets mention the exploitation of the "copper of the mountains" and this may refer to "natural" brass. "Oreikhalkon" (mountain copper), the Ancient Greek translation of this term, was later adapted to the Latin aurichalcum meaning "golden copper" which became the standard term for brass. In the 4th century BC Plato knew orichalkos as rare and nearly as valuable as gold and Pliny describes how aurichalcum had come from Cypriot ore deposits which had been exhausted by the 1st century AD. X-ray fluorescence analysis of 39 orichalcum ingots recovered from a 2,600-year-old shipwreck off Sicily found them to be an alloy made with 75–80% copper, 15–20% zinc and small percentages of nickel, lead and iron.
ISO 17025 calibration Calibration of a density meter by an officially accredited lab is the only way to be sure that measurements are traceable back to national standards, such as the International System of Units (SI), globally comparable, and true. See our article on ISO 17025 calibration as well.
Temperature A material’s volume and state changes with temperature. Temperature therefore has an important influence on the density. Consequently, an accurate density measurement requires accurate temperature determination and good temperature stability. An excellent example of the temperature dependence of density is the thermometer. With increasing temperature, the volume of alcohol inside the thermometer expands and rises. Same mass but more volume means less density. Temperature is a vital factor for precise density measurement, in which you need precise temperature control or algorithms for compensation. A temperature difference of 0.1 °C might result in a density error of up to 0.0001 g/cm³.