ค้นเจอ 21 รายการ

Magnetite

แปลว่า(Concrete Engineering) An aggregate used in heavy weight concrete, consisting primarily of ferrous metaferrite (Fe304). A black magnetic iron ore with a specific gravity of approximately 5.2 and a Mohs hardness of about 6.

Age Hardening

แปลว่า(english) Hardening by aging, usually after rapid cooling or cold working. The term as applied to soft, or low carbon steels, relates to a wide variety of commercially important, slow, gradual changes that take place in properties of steels after the final treatment. These changes, which bring about a condition of increased hardness, elastic limit, and tensile strength with a consequent loss in ductility, occur during the period in which the steel is at normal temperatures.

Brinell Hardness Test

แปลว่า(english) A common standard method of measuring the hardness of materials. The smooth surface of the metal is subjected to indentation by a hardened steel ball under pressure. The diameter of the indentation, in the material surface, is then measured by a microscope and the hardness value is read from a chart or determined by a prescribed formula.

Brinell Hardness Number

แปลว่า(english) The value of hardness of a metal on an arbitrary scale representing kg/mm2, determined by measuring the diameter of the impression made by a ball of given diameter applied under a known load. Values are expressed in Brinell Hardness Numbers, BHN

BHN

แปลว่า(english) Brinell Hardness Number

Aging 1

แปลว่า(english) A change in the properties of certain metal and alloys (such as steel) that occurs at ambient or moderately elevated temperatures after a hot working heat treatment or cold working operation. Typical properties impacted are hardness, yield strength, tensile strength, ductility, impact value, formability, magnetic properties, etc. See also Non-aging.

Brown Sharp Gages

แปลว่า(english) A standard series of sizes refered to by numbers, in which the diameter of wire or thickness of sheet metal is generally produced and which is used in the manufacture of brass, bronze, copper, copper-base alloys and aluminum. These gage numbers have a definite relationship to each other. In this system, the decimal thickness is reduced by 50% every six gage numbers- while temper is expressed by the number of B&S gage numbers as cold reduced in thickness from previous annealing. For each B&S gage number in thickness reduction, where is assigned a hardness value of 1/4 hard.

Brale

แปลว่า(english) A diamond penetrator, conical in shape, used with a Rockwell hardness tester for hard metals.

Brinell Hardness Testing

แปลว่า(english) Method of determining the hardness of materials; involves impressing a hardened ball of specified diameter into the material surface at a known pressure (10-mm ball, 500-kg load for aluminum alloys). The Brinell hardness number results from calculations involving the load and the spherical area of the ball impression. Direct-reading testing are generally used for routine inspection of forgings, and as a heat treat control function.