Corrosion behavior and magnetocaloric effect of FeNi(1J85) coated LaFe_(11.6)Si_(1.4)/Sn composites

The FeNi coated LaFe_(11.6)Si_(1.4)/Sn composites were prepared by hot pressing(HP). The microstructure,corrosion behavior and magnetocaloric effect(MCE) of FeNi coated LaFe_(11.6)Si_(1.4)/Sn composites were investigated systematically. The results show that the corrosion resistance of FeNi coated LaFe_(11.6)Si_(1.4)Sn composites is better than that of LaFe_(11.6)Si_(1.4)/Sn composites in deionized water. The maximum magnetic entropy change((-△S_M)^(max)) and relative cooling power(RCP) of FeNi coated LaFe_(11.6)Si_(1.4)/Sn composites are 13.30 J/(kg-K) and 146.25 J/kg, respectively, which are larger than that((-△S_M)^(max), 10.65 J/(kg·K) and RCP, 106.53 J/kg) of LaFe_(11.6)Si_(1.4)/Sn composites in a low magnetic field change of 2 T. FeNi coated LaFe_(11.6)Si_(1.4)/Sn composites possess a more negative slope. The improvement of magnetic properties is due to high permeability FeNi permalloy(1 J85) which improves the itinerant-electron metamagnetic(IEM) transition. So, the method of coating FeNi can provide a new idea for enhancing the corrosion resistance and magnetocaloric effect of La(Fe_xSi_(1-x))_(13)-based materials.

压力对热压法制备LaFe_(11.6)Si_(1.4)H_(1.02)-In复合材料组织与性能的影响（英文）

主动式磁蓄冷器中的制冷材料需要满足优良的机械性能、磁热性能和导热性能。然而,目前大多数磁制冷材料在成形和导热性能方面存在着一些问题。在本研究中,介绍了一种在430 K的温度下,将LaFe_(11.6)Si_(1.4)H_(1.02)和铟粉混合后在不同压力下进行压制成形的方法。结果显示,当压制压力超过200 MPa时,复合磁工质的磁热性能将会大幅度降低。在压制压力为100 MPa时,厚度为0.8 mm的片状磁工质在0~2 T的磁场下,达到的最大绝热温变为5.88 K。