| Addition Agent | (english) 1) Any material added to a charge of molten metal in bath or ladle to bring alloy to specifications, 2) reagent added to plating bath. |
| Adeline Steelmaking Process | (english) Method of producing a precision casting of steel or steel alloys using aluminolthermic process and lost wax, followed by centrifugal action. |
| Aecm, Ae1, and Ae3 | (english) Equilibrium transformation temperatures in steel. |
| AFS Tests | (english) A number of standard tests determined by American Foundrymen's Society to evaluate molding and core sands. |
| Age Hardening | (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. |
| Agglomerating Processes | (english) "Fine particles of limestone (flux) and iron ore are difficult to handle and transport because of dusting and decomposition, so the powdery material usually is processed into larger pieces. The raw material's properties determine the technique that is used by mills. 1) SINTER Baked particles that stick together in roughly one-inch chunks. Normally used for iron ore dust collected from the blast furnaces. 2) PELLETS Iron ore or limestone particles are rolled into little balls in a balling drum and hardened by heat. 3) BRIQUETTES Small lumps are formed by pressing material together. Hot Iron Briquetting (HBI) is a concentrated iron ore substitute for scrap for use in electric furnaces. |
| Aging 1 | (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. |
| Aging 2 | (english) A change in properties that occurs at ambient or moderately elevated temperatures after hot working or a heat treating operation (quench aging in ferrous alloys), or after a cold working operation (strain aging). The change in properties is often, but not always, due to a phase change (precipitation), but does not involve a change in chemical composition. In a metal or alloy, a change in properties that generally occurs slowly at room temperature and more rapidly at higher temperatures. |
| AIR BLEEDER AUTOMATIC | (english) A valve that is fit into a hydraulic pipeline to facilitate automatic release of air trapped in the pipeline. See also AIR BLEEDER, MANUAL. |
| Ball Piston Pumps | (english) The Ball Piston Pump is a very simple pump design. It has a rotor which revolves around an internal stator. The rotor has twelve cylinders machined out of it, and each cylinder has a ball inside which can slide in and out of the cylinder. |