本文对多晶NiAl以及不同粒径的NiAl样品的磁性进行了研究．结果表明：大块多晶NiAl合金的磁化率X很小．大约为3×10－5／g，其比磁化强度σ几乎不随温度变化，在1．5－150K温度范围，平均粒径为8．6nm的制备态纳米NiAl的σ随温度的增高而显著下降，由σ-T曲线可得到其居里温度Tc为124K．制备态的纳米NiAl经退火处理后得到的平均粒径分别为12，18和21nm的三种样品的σ比普通多晶NiAl高两个量级，而且在1．5—300K温度范围，σ随温度变化很小．表明多晶NiAl合金在其晶粒纳米化后发生了非磁性－磁性转变。
The magnetism of bulk polycrystal NiAl and nanostructural NiAl with various grain diameter was studied. The susceptibility of a bulk polycrystal NiAl X is about 3.0×10-3 / g, its specific magnetization σ has almost not change with temperature. The σof as condensed nanostructural NiAl samples with average grain size of 8.6 nm, diminishes obviously with the increase in temperature at a range of 1.5 -150 K, from tis σ-T curve we get the Curie temperature TC of the sample being about 124 K. Other three samples obtained by annealed the condensed NiAl samples at various temperatures have average grain sizes of 12,18 and 21 nm, their a are two orders of magnitude larger than that of the bulk polycrystal NiAl, change slightly with temperature at range of 1.5-300 K. The experimental results indicate that there exists nonmagnetism-magnetism transition between polycrystal NiAl alloy and nanostructural NiAl.
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| [1] | |
| [2] | |
| [3] | |
| [4] | |
| [5] | |
| [6] | |
| [7] |
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