时间:2011-03-11 23:13来源:蓝天飞行翻译 作者:admin 点击:次
fermium. A synthetic, metallic, radioactive chemical element. Fermium’s symbol is Fm, its atomic number is 100, and it has mass numbers ranging between 248 and 257. Fermium was first discovered as debris from a hydrogen bomb explosion, and it is now made in nuclear reactors. ferrite. A material used as a core for many electromagnetic components. Ferrite is made of powdered metal sintered and molded into the proper shape. Sintering is a process in which powdered metal is heated but not quite melted, and then squeezed together. Ferrite has a high permeability, it easily accepts lines of magnetic flux, but it has such a high resistance that eddy current losses are very low. ferrite steel. Alpha iron into which some carbon has been dissolved. It exists at temperatures below its critical temperature. ferromagnetic material. A material that contains iron and has a high magnetic permeability. Ferromagnetic materials can be magnetically saturated (all the magnetic domains aligned in the same direction). They have good retentivity; they retain a large amount of their magnetism when the magnetizing force is removed. ferrous metal. Any metal that contains iron and has magnetic characteristics. Magnetic characteristics include the ability to be magnetized and to be attracted by a magnet. ferrule resistor (electrical component). A type of resistor that has metal ferrules, or bands, around each end so it can be mounted in a standard fuse clip. ferrule terminals (electrical fuse component). The terminals on each end of a tubular fuse. Ferrule terminals are short, closed, metal caps that slip over the ends of a glass tube that contains a fuse link. The ferrule terminals are held in fuse clips. FHP (friction horsepower). The amount of horsepower used to turn the crankshaft, pistons, gears, and accessories in a reciprocating engine and to compress the air inside the cylinders. |