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The effects of the introduction of Ce to La_(1-x)Ce_xFe_(11.5)Si_(1.5) alloys on 1:13 phase formation mechanism,the first-order magnetic phase transition strengthening characteristics,and magnetocaloric property were studied,respectively.The results show that the formation mechanisms of 1:13 and La Fe Si phases in La_(1-x)Ce_xFe_(11.5)Si_(1.5) alloys are the same as those of Ce_2Fe_(17) and CeFe_2 phases in Ce–Fe binary system,respectively.The substitution of Ce in 1:13 phase which is limited can make the first-order magnetic phase transition characteristics strengthen,which can make thermal and magnetic hysteresis increase,the temperature interval of temperatureinduced phase transition decrease,and the critical magnetic field of field-induced magnetic phase transition(HC)increase,respectively.Owing to the lattice shrink of 1:13phase with the increase in Ce content,the Curie temperatures(TC) show a linear decrease.The maximum change in magnetic entropy gradually increases due to the decrease in temperature interval of temperature-induced phase transition,but the relative cooling capacities are all about80 Jákg-1at magnetic field of 2 T.
The effects of the introduction of Ce to La_ (1-x) Ce_xFe_ (11.5) Si_ (1.5) alloys on 1:13 phase formation mechanism, the first-order magnetic phase transition strengthening characteristics, and magnetocaloric property were studied, results show that the formation mechanisms of 1:13 and La Fe Si phases in La_ (1-x) Ce_xFe_ (11.5) Si_ (1.5) alloys are the same as those of Ce_2Fe_ (17) and CeFe_2 phases in Ce-Fe binary system , respectively. The substitution of Ce in 1:13 phase which is limited can make the first-order magnetic phase transition characteristics enhance, which can make thermal and magnetic hysteresis increase, the temperature interval of temperature induced phase transition decrease, and the critical magnetic field of the field-induced magnetic phase transition (HC) increase, respectively. Ofwing to the lattice shrink of 1: 13phase with the increase in Ce content, the Curie temperatures (TC) show a linear decrease.The maximum change in magnetic entropy gradually increases due to the decrease in temperature interval of temperature-induced phase transition, but the relative cooling capacities are all about 80 Jákg-1at magnetic field of 2 T.