摘要
采用DTA分析Ti-23Al-25Nb合金和Ti-23Al-25Nb-0.36Y合金的相变特征,并根据DTA曲线特征制定热处理工艺,用SEM,XRD分析热处理后合金试样的显微组织及相组成,用TEM分析原始组织中钇的存在形式,用Instron-5569万能材料试验机进行室温压缩试验。结果表明,钇在原始组织中以Y2O3形式存在;钇没有改变Ti-23Al-25Nb合金的相变温度;加入钇后,在1320℃淬火,B2相晶粒比较粗大,随着淬火温度的降低,O相增加,并且O相板条变细而杂乱,有利于提高合金的塑性和抗蠕变性能;加入钇后,合金强度提高,原因是第二相粒子Y2O3弥散强化的结果。
Characteristics of phase transformations of Ti-23Al-25Nb alloy and Ti-23Al-25Nb-0.36Y alloy were analyzed by DTA. Heat treatment conditions of these alloys were worked out according to the DTA results. The microstructures and phase analysis of these alloys were analyzed by means of SEM and XRD. The existence state of Y in the original microstructure was determined by means of TEM. Room temperature compression tests were carried out on the Instron-5569 machine. Research results show that Y in the original structure exists in the form Of Y2O3, but it does not change the phase transformation temperature of Ti-23Al-25Nb alloy. After quenching at 1320 degrees C, the grain sizes of B-2 phase in Ti-23Al-25Nb-0.36Y alloy are coarser than those in Ti-23AI-25Nb alloy. With decreasing of quenching temperature, the amount of O phase increases, and its plates are thinned and more cluttered. Adding of Y increases the strength of the alloy, which is attributed to the dispersion strengthening of second phase particles of Y2O3.
出处
《稀有金属材料与工程》
SCIE
EI
CAS
CSCD
北大核心
2006年第4期655-658,共4页
Rare Metal Materials and Engineering
基金
国家自然科学基金资助项目(50274035)
