Room temperature magnetic refrigerator using both metal Gd or/and Gd-Si-Ge alloys and a permanent magnetic field source

A room temperature magnetic refrigerator using both metal Gd or/and Gd-Si-Ge alloys and permanent magnetic field source was introduced in the present paper. The permanent magnet was assembled in a shape of cylinder in which there are 1.4 Tesla uniform magnetic fields. A temperature span of 25 K was reached for the alloys when environment temperature was about 290 K. But if the alloys are short of Ga, the less temperature range could be reached at the same temperature. In addition, the magnetic refrigerator was also filled with metal Gd as the refrigerant; a temperature span of 26 K was reached.