本文报道一种fcc结构的Fe-Mn-Al合金(Mn 25.6,Al 4.1,C 0.16,Si0.27 wt-％)在超低温的性能、组织结构与磁性转变。此合金在300—4 K间具有适宜的强度、较高的塑性、韧性与很稳定的奥氏体组织。300 K及4 K的磁化率x_v,分别为34.5×10~(-4)与22×10~(-4)。室温电阻率为105μΩ·cm,低温冷收缩率小于一般Fe-Cr-Ni奥氏体钢。其磁化率(x_v)-温度(T)曲线于320 K左右呈现峰值,dx/dT符号的改变表征发生了顺磁性-反铁磁性转变。同时伴有一些物理性能如弹性模量、热膨胀、电阻率等的反常变化。 Al加入Fe-Mn合金中,明显地降低Néel温度(T_N),提高磁化率,并在T_N点处呈现较大的磁化率峰值。与AISI 300系Cr-Ni奥氏体钢比较,γ-Fe-Mn-Al合金的主要特点为在极低温区(如20—4 K)兼具稳定的奥氏体与极低磁化率,是一种潜在的超导磁体用结构合金。
Studies were made of the cryogenic properties, structural stability and magnetism transition of a fcc γ-Fe-Mn-Al alloy containing 25.6% Mn,4.1%Al, 0.16%C and 0.27%Si, of which the strength, ductility and austenitic stability are satisfactory at temperature range of 300 to 4 K. Its physical properties were determined as follows: lower magnetic susceptibility about 34.6×10~(-4) to 22×10~(-4) from 300 to 4 K; higher electric resistivity up to 105μΩ·cm and lower cold contraction than conventional Fe-Cr-Ni austenitic steels. A peak value is presented on the plot of temperature T dependence of magnetic susceptibility x at 320 K. The sign change of dx/dT shows the paramagnetism-antiferromagnetism transition at which an anomaly of several physical properties such as elastic modulus, heat expansion, etc. is accompanied. Furthermore, by an addition of Al to Fe-Mn alloy, its Néel temperature may be markedly lowered. The magnetic susceptibility may be increasing to a greater value at Néel temperature. In comparison with AISI 300 Cr-Ni austenitic stainless steels, the γ-Fe-Mn-Al alloy is characterized by both stable austenite and quite low magnetic susceptibility within temperature range down from 20 to 4 K. It seems to be a potential constructional material for superconducting magnet applications.
参考文献
| [1] | |
| [2] | |
| [3] | |
| [4] | |
| [5] | |
| [6] | |
| [7] | |
| [8] | |
| [9] | |
| [10] | |
| [11] | |
| [12] | |
| [13] | |
| [14] | |
| [15] |
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