摘要
用差热分析(DTA),结合X射线衍射(XRD)研究了Nd—Dy—Fe—Co—B非晶合金的晶化动力学。结果表明,温度低于800℃不同升温速率的升温过程中,合金Nd_(7.5)Dy_(1.5)Fe_(70)Co_(16)B_5中先后出现三个晶化相:软磁相α—Fe相、亚稳相Nd_2Fe_(23)B_3和硬磁相Nd_2Fe_(14)B_o三个晶化相的晶化激活能随晶化份数的增加而降低。α—F相的表观激活能为98.09KJ/mol,Nd_2Fe_(23)B_3和Nd_2Fe_(14)B的分别为131.79KJ/mol和129.20KJ/mol。Nd_2Fe_(14)B和α—Fe相的晶化行为表明Nd_(7.5)Dy_(1.5)Fe_(70)Co_(16)B_5合金退火时容易形成晶粒粗大的Nd_2Fe_(14)B/α—Fe微结构的原因,是Nd_2Fe_(14)B和α—Fe相都容易长大造成的。
The crystallization kinetics of amorphous Nd-Dy-Fe-Cb-B alloy have been investigated by DTA and XRD. During the alloy is heated to 800℃ , the crystalline phases appearing in the alloy are a - Fe phase, Neb Fe23 B3 and Nd2 Fe14 B. The crystallization activation energy of a - Fe phase, Nd2 Fe23 B3 and Nd2 Fe14 B all declines with increasing the crystallized fraction. The apparent crystallization activation energy of a - Fe phase is 98. 09 kJ/ mol,the apparent crystallization activation energys of Nd2Fe23B3and No2Fe14 separately 131. 79kJ/mol and 129. 20kJ/mol. The crystallization behavior of the a - Fe phase and Nd2Fe14 B essentially results in the formation of an Nd2 Fe14 B/α - Fe composite microstructure with a coarse grain size in annealed Nd7.5Dy1.5Fe70Co16B5 alloy, which is attributed to an easy growth of both α - Fe phase and Nd2Fe14B in the alloy.
出处
《物理测试》
CAS
2001年第4期14-17,共4页
Physics Examination and Testing
基金
国家自然科学基金19974035
河北省自然科学基金597188
