铸态Ti-43Al-9V-0.3Y合金由γ相及少量α2, B2和YA2相组成, 为细小的近层片组织, 晶粒(层片团)尺 寸约为80 um, 层片体积分数约为85 %; 锻态合金由大量细小的动态再结晶等 轴γ晶粒组成, 组织细化显著, γ再 结晶晶粒尺寸约为1-5 um; 轧态合金为细小近γ组织, γ晶粒尺寸约为20um, 尺寸细小的B2相呈网络状分布在γ晶粒周围. 铸态合金在室温下的拉伸断裂强度约为510.6 MPa, 延伸率约为0.5%; 在700 ℃下的拉伸断裂强度约为425.8 MPa, 延伸率约为5.7%. 锻造和轧制后的Ti-43Al-9V-0.3Y合金的力学性能均得到了明显改善.
As-cast Ti-43Al-9V-0.3Y alloy is mainly comprised of γ phase, besides minor α2, B2 and YAl2. The alloy is fine-grained and mainly consists of lamellar structure (approximately 85 vol%). The mean colony size is about 80 μm. There is evidence of the β phase and γ phase along colony boundaries and disperse fine YAl2 particles. There exist some B2 precipitations within the lamellar colonies. As-forged Ti-43Al-9V-0.3Y alloy has the streamline near gamma (NG) microstructure drastically refined with DRX γ grains of 1~5μm. The B2 and YAl2 phases are broken and elongated and the lamellar colonies diminish. As-rolled Ti-43Al-9V-0.3Y alloy has the fine NG microstructure with γ grains of about 20μm. The streamline structure vanishes. The B2 phases with size of 8μm are distributed in the network shape along γ grains and the YAl2 particles are disperse. As-cast Ti-43Al-9V-0.3Y alloy has the ultimate tensile strength of about 510.6 and 425.8MPa, the elongation of 0.5% and 5.7%, at room temperature and 700℃, respectively. After forging and rolling, the tensile properties are greatly improved. At room temperature, the strength of as-forged and as-rolled material increases about 89~132MPa, and the elongation increases from 0.5% to 1% and 1.2%, respectively. At 700℃, the strength as-rolled material increases about 63~72MPa and the elongation increases from 5.7% to 7.9%. The improvement of the tensile properties is attributed to the microstructural refinement and higher density induced by forging and rolling process.
参考文献
| [1] | |
| [2] | |
| [3] | |
| [4] | |
| [5] | |
| [6] | |
| [7] |
- 下载量()
- 访问量()
- 您的评分：
-
10%
-
20%
-
30%
-
40%
-
50%