采用近等温锻造开坯工艺实验定量研究了增大变形量对Ti-46.5Al-2.5V-1.0Cr-0.3Ni合金变形组织均匀性和力学性能稳定性的作用.通过锻坯组织观察分析及硬度、强度分布测试,揭示了TiAl合金近等温锻造过程中变形量与宏观组织和微观组织均匀性的基本关系.结果表明:近等温锻造变形量为65％,70％,75％,80％,85％时,随着变形量的增大,TiAl合金锻坯内的宏观变形流线分布趋于均匀,均匀变形区域面积不断增大,变形量85％时均匀变形区面积增加至68.0％,微观变形组织由等轴的γ和α2,以及很少量的残余层片团组成,晶粒尺寸明显细化,且等轴组织在合金中占到了绝大部分；锻坯硬度分布测试表明随着近等温锻造变形量的增大,均匀变形区域的硬度变化基本趋于均匀一致,且硬度平均值也在不断增高；锻坯难变形区和均匀变形区经1250℃/15h/AC热处理后取样进行室温压缩测试,随着近等温锻造变形量的增加锻坯各部位室温压缩应力应变数据分散度降低,性能稳定性提高.
参考文献
| [1] | SEMIATIN S L.Wrought processing of ingot-metallurgy gamma titanium aluminide alloys[A].Warrendale:TMS,1995:509-524. |
| [2] | J.Yamaguchi;H.Inui .High-temperature structural intermetallics[J].Acta materialia,2000(1):307-322. |
| [3] | SEMIATIN S L;SEETHARAMAN V;JAIN V K .Microstructure development during conventional and isothermal hot forging of a near-gamma titanium aluminide[J].Metallurgical and Materials Transactions A:Physical Metallurgy and Materials Science,1994,25A(12):2753-2768. |
| [4] | FUJIWARA T;NAKAMURA A;HOSOMI M et al.Deformation of polysynthetically twinned crystals of TiAl with a nearlystoichiometric composition[J].Philosophical Magazine A:Physics of Condensed Matter:Structure,Defects and Mechanical Properties,1990,61(04):591-606. |
| [5] | 张永刚;韩雅芳;陈国良.金属间化合物结构材料[M].北京:国防工业出版社,2003 |
| [6] | SI Jia-yong,HAN Peng-biao,ZHANG Ji.Design for Isothermal Forging of Ti-46. 5Al-2.5V-1.0Cr-0.3Ni Alloy[J].钢铁研究学报（英文版）,2010(08):67-73. |
| [7] | SEMIATIN S L;CHESNUTT J C;AUSTIN C.Processing of intermetallic alloys[A].Warrendale:TMS,1997:263-276. |
| [8] | SEETHARAMAN V;SEMIATIN S L .Plastic-flow and microstructure evolution during hot deformation of a gamma titanium aluminide alloy[J].Metallurgical and Materials Transactions A:Physical Metallurgy and Materials Science,1997,28A(11):2309-2321. |
| [9] | 司家勇,高帆,张继.变形方向对TiAl合金二次热变形行为的影响[J].材料工程,2010(12):51-54,65. |
| [10] | 汪大年.金属塑形成形原理[M].北京:机械工业出版社,1982 |
| [11] | KIM Y W .Strength and ductility in TiAl alloys[J].Intermetallics,1998,6(07):623-628. |
| [12] | SEMIATIN S L;SEETHARAMAN V;WEISS I.Hot working of titanium alloys-an overview[A].Warrendale:TMS,1997:3-73. |
上一张
下一张
上一张
下一张
计量
- 下载量()
- 访问量()
文章评分
- 您的评分：
-
10%
-
20%
-
30%
-
40%
-
50%