摘要本文采用Ti-45Al-8Nb合金与Ti-45Al-6Nb-0。4W合金作为实验材料，利用感应悬浮熔炼法制备合金纽扣铸锭，并用电弧炉将纽扣铸锭重力铸造成圆柱棒状试样，利用光学浮区法，分别制备Ti-45Al-8Nb合金在10、12和15mm/h三种不同的生长速率下获得稳定生长的定向凝固合金试样，以及Ti-45Al-6Nb-0。4W合金在10和15mm/h两种不同生长速率下获得的稳定生长的定向凝固合金试样。

分析可得，对于Ti-45Al-8Nb合金，生长速率在10mm/h～15mm/h范围内时，随着生长速率降低，稳定生长区获得单晶的可能性越大；光学浮区定向凝固Ti-45Al-8Nb合金、Ti-45Al-6Nb-0。4W合金的片层组织中出现了B2相，这是由于高含量的β稳定元素Nb、W所致；片层取向为0°的光学浮区法定向凝固Ti-45Al-6Nb-0。4W合金具有最好的综合力学性能。87889

毕业论文关键词  定向凝固  生长速率  单晶  光学浮区法 

毕业设计说明书外文摘要

Title    Study on preparation and microstructure of TiAl alloy oriented single crystal

Abstract This paper uses Ti-45Al-8Nb alloys and Ti-45Al-6Nb-0。4W alloy as experimental material, using induction levitation melting method button alloy ingot preparation, and use of electric arc furnace will button ingot gravity casting into a cylindrical rod specimens, with optical floating zone method, preparing Ti-45Al-8Nb alloys under 10, 12, and 15mm/h three kind of different growth rate to obtain a stable growth of directionally solidified superalloy specimens were prepared, and Ti-45Al-6Nb-0。4W alloy in 10 and 15mm/h two different growth rate to obtain the stable growth of directionally solidified superalloy specimen。

According to analysis, for Ti-45Tl-8Nb alloys, the growth rate in the 10mm/h to 15mm/h range, decrease with increasing growth rate, stable growth area obtained single crystals of the greater the possibility; appearance lamellar tissue optical floating zone directional solidification Ti-45al-8nb alloys, Ti-45Al-6Nb-0。4W alloy of B2 phase, which is due to the high content of beta stable elements Nb; alignment layer as zero degree optical floating zone legal to solidification Ti-45Al-6Nb-0。4W alloy has the best comprehensive mechanical properties。

Keywords  directional solidification   solidification  velocity   single crystal    optical floating zone method

目   次

1  绪论 1

1。1  研究背景 1源-于,优Y尔O论U文.网wwW.youeRw.com 原文+QQ75201,8766

1。2  TiAl合金的组织与性能 1

1。2。1  TiAl合金二元相图 2

1。2。2  TiAl基合金显微组织与力学性能 2

1。3  TiAl合金的定向凝固 4

1。3。1  定向凝固技术 4

1。3。2  TiAl合金显微组织片层取向的控制 5

1。3。3  合金元素对钛铝合金定向凝固的影响 6

1。4  本课题研究的内容 7

2  实验方法及样品制备 8

2。1  实验材料选择及试验设备 8

2。1。1  实验材料 8

2。1。2  仪器设备 8

2。1。3  光学浮区定向凝固系统 9

2。1。4  分析方法与分析设备