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Magnetic refrigeration technology developed in recent years for its environmental protection, energy saving has been widespread concern, there have been alternative gas compression refrigeration trend. Magnetic refrigeration technology, a key question is found in different temperature ranges with large magnetocaloric effect of magnetic refrigeration materials. Existing research results show, La (Fe x Si 1-x ) 13 and Gd 5 Si < sub> 2 Ge 2-x Fe x in different temperature zones is an ideal magnetic refrigerant materials. The experimental analysis by X-ray diffraction, SEM observation, EDS analysis, MT and MH curves measured studied La (Fe x Si 1-x ) 13 and Gd 5 Si 2 Ge 2-x Fe x series alloys of different compositions organizational structure and magnetic refrigeration performance. The results show that La (Fe x Si 1-x ) 13 (x = 0.88,0.89,0.90,0.91,0.92) series alloys , with the Fe content increases tissue strips decreased; in Gd 5 Si 2 Ge 2-x Fe x (x = 0, 0.25, 0.5, 0.75, 1) series alloys, the Fe content increases with the grain boundary becomes more apparent. For Gd 5 Si 2 Ge 2-x Fe x (x = 0.25, 0.5, 0.75, 1) conducted a micro-component analysis showed that the substitution of Fe on Ge occurs mainly in the grain boundary segregation. Experimentally measured won La (Fe x Si 1-x ) 13 (x = 0.88,0.89,0.90,0.91,0.92) Curie temperature, Fe content increases makes the Curie temperature decreased; selecting the appropriate temperature measured La (Fe x Si 1-x ) 13 (x = 0.88,0.89,0.90,0.91) series alloy samples MH curve, and calculate the alloy maximum magnetic entropy change. The results show that when x = 0.90 at 188K near the Curie temperature of maximum magnetic entropy change 26.75J / (kg ยท K); experimentally measured won Gd 5 Si 2 Ge 2-x Fe x (x = 0, 0.25, 0.5, 0.75, 1) Curie temperature series alloys, Fe substitution of Ge makes the Curie temperature rise; Select the appropriate temperature measurement of Gd 5 Si 2 Ge 2-x Fe x (x = 0, 0.25, 0.5, 0.75) series alloy samples MH curve, and calculated the maximum magnetic entropy change of the alloy, the results show that the substitution of Fe on Ge although the Curie temperature can be improved, but results in the maximum magnetic entropy change decreases.
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