X.L. Xu
,
Z.W. Yu
,
S.J. Ji
金属学报(英文版)
Decomposition processes of the quenched Zn-Al alloys were studied by differentiai scanning calorimetry (DSC), X-ray diffraction (XRD) and transmission electron microscopy (TEM). The results show that the stabilities of supersaturated solid solution (SSS) of Zn-Al alloy and c' phase formed by quenching would reduce with increasing Zn content and precipitating η-Zn phases even when aging at ambient temperature,so that exothermic precipitation peak in DSC curve would disappear. The activation energy of the η-Zn precipitation and their reaction enthalpy were calculated and measured. The kinetics of α' decomposition or η-Zn formation was determined by XRD.The microstructure change during aging was observed by TEM.
关键词:
differential scanning calorimetry (DSC)
,
null
,
null
,
null
迟广成
,
殷晓
,
伍月
,
邵九龙
冶金分析
doi:10.13228/j.boyuan.issn1000-7571.009717
因榍石在变质岩中含量太少，晶体光学特征不明显，利用偏光显微镜及X射线衍射（X RD ）等鉴定技术不易确定。实验利用扫描电镜／能谱仪检测矿物所含元素的种类，确定各元素的大致含量，根据定性分析结果，调用相应的标准样品数据文件，建立所测样品的文件清单。运用Casino程序和Quanta程序，据所测元素的强度值计算出样品中各元素的质量分数，依据矿物化学式中阴阳离子电价平衡的配比规律，计算出所测样品的化学组成。分析结果表明，所测8个样品中 SiO2质量分数在33.36％～34.10％之间，CaO 质量分数在25.85％～27.00％之间，（TiO2＋Fe2 O3＋Al2 O3＋CrO2）质量分数在39.31％～40.45％之间，与榍石主要化学成分基本一致。实验表明，同一件榍石样品平行测定10次，O、Si、Ca、T i、Fe元素测定结果的相对标准偏差（RSD ）依次为0.23％、0.30％、0.28％、0.26％、1.6％，精密度符合要求；经验证，实验方法的测定结果与电子探针波谱法测定结果相符。
关键词:
变质岩
,
榍石
,
X射线衍射
,
扫描电镜/能谱法
,
化学成分
