کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1600639 1005168 2011 9 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
The effect of Ruthenium addition on the microstructure and mechanical properties of TiAl alloys
موضوعات مرتبط
مهندسی و علوم پایه مهندسی مواد فلزات و آلیاژها
پیش نمایش صفحه اول مقاله
The effect of Ruthenium addition on the microstructure and mechanical properties of TiAl alloys
چکیده انگلیسی

The high temperature compression behavior of TiAl–Ru alloys was studied at different temperatures and strain rates. Ru was found to have a strong strengthening effect on TiAl alloys. However the Ru addition amount was limited by its low solubility in γ-TiAl and α2-Ti3Al, and the detrimental effect of excessive ternary phase precipitation. Furthermore, the melting temperature decreases when Ru ≥0.6 at.% as the alloy composition approaches a ternary eutectic point. The strengthening mechanism is discussed and two separate mechanisms are proposed, viz. solid solution strengthening and refined colony strengthening. Intergranular cracks were found in the alloys with low Ru or no Ru addition, but were barely detected as Ru content increased to above 0.6 at.%. It was suggested that Ru showed a beneficial effect on both strength and ductility of TiAl alloys due to the refined colony size. Three-point bend test results showed that the Ru addition can also improve the room temperature ductility of TiAl alloys. Hot workability was increased according to the compression tests. Thermal-mechanically treated TiAl–Ru had much smaller grain size than the heat-treated samples due to dynamic recrystallization. But it did not show superior strength in the compression test compared to the heat-treated samples. The Zener–Hollomon parameter was calculated from the compression strength of heat-treated TiAl–Ru alloys. Its relationship with dynamic recrystallization and hot work is discussed. The mechanical properties of TiAl–Ru alloys are compared with TiAl–Nb samples and demonstrate a promising combination of strength and ductility.

Figure optionsDownload as PowerPoint slideHighlights
► Ru has a strong strengthening effect on TiAl alloys.
► Ru has limited solubility in TiAl alloys.
► Ru addition will increase the ductility and hot-workability of TiAl alloys.
► Cracks will form in the alloys with no Ru or less Ru addition after heat treatment.
► Zener–Hollomon parameter can be used to control the hot work behavior of TiAl.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Intermetallics - Volume 19, Issue 9, September 2011, Pages 1282–1290
نویسندگان
, ,