稀土(Y、Ce、Sm)对Ni-P非晶态合金热稳定性的影响

用差示扫描量热法(DSC)研究了非晶态合金Ni-RE-P(RE=Y, Ce, Sm,下同)的热稳定性; 用X-光衍射(XRD)和扫描电镜(SEM)检测了在不同温度范围处理的样品的结构变化. 结果表明, 向非晶态Ni-P合金中加入少量稀土元素(Y, Ce, Sm), 可显著提高非晶态Ni-RE-P合金的热稳定性.样品的晶化激活能数据表明, Ni-RE-P的各转变阶段的激活能都比Ni-P的大, 说明Ni-RE-P比Ni-P更难晶化, 即Ni-RE-P比Ni-P更稳定.

EFFECT OF RARE EARTH (Y,Ce,Sm) ON THERMAL STABILITY OF AMORPHOUS Ni-P ALLOY

The thermal stability of amorphous Ni-RE-P(RE=Y,Ce,Sm)alloy has been stu-died by differential scanning calorimetry(DSC)in this paper.X-ray diffraction(XRD)and scanning electron microscope(SEM)were used to examine the structurechange of the samples heated at different temperatures.The results showed that a smallamount of rare earth elements(Y,Ce,Sm)added into amorphous Ni-P alloy could con-siderably enhanced the thermal stability of amorphous Ni-RE-P alloy.For example,only one exothermic peak appeared at 629K for Ni-P,while the temperature of ma-ximum exothermic peak which was regarded as crystallization of amorphous Ni-Y-P,Ni-Ce-P and Ni-Sm-P alloys was at 786K,795K and 742K respectively.With in-creasing of the treatment temperature,the amorphous Ni-P and Ni-RE-P alloys wereprogressively crystallized to be simultaneous with presentation of the fine crystals Niand Ni_3P and the fine crystals grew up to greater crystalline particles due to aggre-gation of them in the bulk.It was showed that the value of activation energy of the crystallization of Ni-RE-P was much greater than that of Ni-P,this indicated that the crystallization of Ni-RE-P was more difficult than that of Ni-P.A small amount of rare earth element(Y,Ce,Sm)played an important role in enhancing the thermal stability of amor-phous Ni-RE-P alloy.