采用纯度为99%的低纯稀土金属Gd经电弧炉熔炼获得Gd5Si2Ge2母合金,然后通过快淬研究快淬工艺对低纯Gd5Si2Ge2合金结构与磁熵变的影响.粉末衍射结构分析表明,铸态Gd5Si2Ge2合金由Gd5Si2Ge2相、Gd5(Si、Ge)3相和Gd(Si、Ge)相所组成;而甩带速度为25、40m/s的合金均为Gd5Si4型正交相.用最小二乘法计算得两种不同快淬速度合金的晶格常数没有明显差异.甩带速度为40m/s的Gd5Si2Ge2合金的居里温度(Tc＝305K)在室温区间,等温磁熵变为7.25J/kg·K(0～5T).
参考文献
| [1] | Smith G S;Tharp A G;Johson Q .[J].Nature,1966,21:1148-1149. |
| [2] | Holtzberg F;Gambino R J;Meguire T R .[J].Journal of Physics and Chemistry of Solids,1967,28:2283-2289. |
| [3] | Pecharsky VK;Gschneidner KA .Giant magnetocaloric effect in Gd-5(Si2Ge2)[J].Physical review letters,1997(23):4494-4497. |
| [4] | Pecharsky VK;Gschneidner KA .Tunable magnetic regenerator alloys with a giant magnetocaloric effect for magnetic refrigeration from similar to 20 to similar to 290 K[J].Applied physics letters,1997(24):3299-3301. |
| [5] | Pecharsky V K;Gschneidner K A Jr.[J].Journal of Magnetism and Magnetic Materials,1997(167):L179-184. |
| [6] | Pecharsky A O;Pecharsky V K;Gschneidner K A Jr.[J].Journal of Alloys and Compounds,2000(338):126-135. |
| [7] | Fu Hao;Teng Baohua;Tang Yongbai.[J].Journal of Functional Materials,2003(34):29. |
| [8] | Von Ranke P J;De Oliveira N A;Gama S.[J].Journal of Magnetism and Magnetic Materials,2004(277):78-83. |
| [9] | 付浩;涂铭旌;陈云贵.[J].稀有金属材料与工程,2004 |
| [10] | Pecharsky A O;Pecharsky V K;Gschneidner K A Jr.[J].Journal of Applied Physics,2003(93):4722. |
| [11] | Gama S;Alves CS;Coelho AA;Ribeiro CA;Persiano AIC;Silva D .On the determination of the phase composition of the Gd5Ge2Si2 alloy[J].Journal of Magnetism and Magnetic Materials,2004(0):848-849. |
| [12] | Massalski T B.Binary Alloy Phase Diagrams[M].ASM:Materials Park,OH,1990:1882. |
| [13] | Choe W.;Pecharsky AO.;Gschneidner KA.;Young VG.;Miller GJ.;Pecharsky VK. .Making and breaking covalent bonds across the magnetic transition in the giant magnetocaloric material Gd-5(Si2Ge2)[J].Physical review letters,2000(20):4617-4620. |
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