Samarium permanent

Samarium salts are used in optical glass, capacitors, thermoionic generating devices, and in sensitizers of phosphors. The metal is doped with calcium fluoride crystals for use in lasers. It also is used along with other rare earths for carbon-arc lighting. Its alloys are used in permanent magnets. 

Seccand example - In the production of samariumcobalt permanent magnets impurities have practically only a dilution effect. One can therefore use instead of a 99.9 % pure samarium metal a significantly cheaper 90 %, perhaps even 80 % pure metal vdth the balance other rare earths. In any case, it is necessary in this instance that the conposition of the other rare earth elements be held constant, vdiich is not always quite so siitple. 

In the early 1970 s when samarium-cobalt magnets were first being proposed as a replacement for platinum-cobalt in microwave tubes, few could have anticipated the success that was to follow. Notwithstanding the traumas brought about by a quadrupling of cobalt prices, their use has grown steadily to the point where they now command a vitally important position in the permanent magnet market. 

Permanent magnets having properties several times superior to any other known materials were developed in 1967. Praseodymium, yttrium, samarium, lanthanum, and cerium are alloyed with cobalt in the range... 

Among the rare-earths, samarium is the most commonly used because it provides the best permanent-magnet property. Other rare-earth elements are sometimes employed in combination with samarium to meet special requirements. The compounds SmCos and Sm2Coi7 are the most important magnetic materials among the cobalt-lanthanide alloys. 

The sealing of a rotating shaft under low leakage conditions is extremely difficult, therefore the stirrer shaft was built completely encapsulated by austenitic material and the transmission of the torque was realised using a permanent magnetic coupling. The magnets were based on samarium-cobalt and are able to transmit a torque of 135 Nm. 

New permanent magnet materials, such as samarium-cobalt and, a fortiori, neodymium-iron-boron alloys, are also of special interest in the design of static devices with specific magnetic-field configurations. Apart from high remanence and coercive force values of magnets made of these materials, Chavanne et al. (1987) emphasize the presence of large anisotropy fields in the conception of these devices. 

EINECS 231-128-7 Samarium. A rare-earth metallic element neutron absorber, dopant for laser crystals, metallurgical research, permanent magnets, mp = 1074° bp = 1794° d = 7.536. Atomergic Chemetats Cerac Phone-Poulenc Sigma-Aldrich Fine Chem. 

Spedding s group at Ames also showed that the rare earths had interesting magnetic properties when the temperature was lowered. As a result, many scientists worked with these metals and learned a great deal about the nature of magnetism. Today the best permanent magnets are made with neodymium or samarium metals as one of the constituents in an alloy. 

The S -band system uses a samarium cobalt permanent magnet, with a fixed field of 1180 G that is swept by a coil over a narrow range of 135 G. This corresponds to a frequency of 3.5 GHz. The system (Figure 3.81) includes an integrated touch screen, internal computer, thermoelectric cooler, and power supply. The instrument is available in an x-band version (9.5 GHz 3480 200 G). 

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