| Journal: | Materials research |
| Database: | PERIÓDICA |
| System number: | 000312394 |
| ISSN: | 1516-1439 |
| Authors: | Duarte, A1 Viana, F Santos, Henrique M.C.M |
| Institutions: | 1Universidade do Porto, Departamento de Engenharia Metalurgica e de Materiais, Porto. Brasil |
| Year: | 1999 |
| Season: | Jul |
| Volumen: | 2 |
| Number: | 3 |
| Pages: | 191-195 |
| Country: | Brasil |
| Language: | Inglés |
| Document type: | Artículo |
| Approach: | Experimental |
| English abstract | Two cast g titanium aluminides, Ti47Al and Ti50Al (at. %), were obtained by arc melting under an argon atmosphere. The as-cast microstructure modification by annealing under protective argon atmosphere and hot isostatic pressing (HIP) was analysed by optical and scanning electron microscopy with microanalysis facilities. As-cast structures presented strong microsegregations, being composed of primary a dendrites (with low Al content), which transformed into lamellar a2 + g during solid state cooling, and interdendritic g phase (with high Al content). Annealing in the a + g field was responsible for a partial reduction of microsegregation, a decreasing of the volume fraction of a2 + g lamellar dendrites, an increasing of g volume fraction and the occurrence of a small fraction of a2 particles and plates in some of the g grains. Annealing in the a field at 1400 °C for one hour was insufficient to eliminate the as-cast microstructure in the Ti50Al alloy and produced large equiaxed lamellar colonies of a2+g in the Ti47Al alloy. HIP in the a + g field (to avoid excessive grain growth) was responsible for microstructure modifications similar to the ones obtained by heat treating under similar soaking conditions |
| Disciplines: | Ingeniería |
| Keyword: | Ingeniería de control, Ingeniería química, Microestructuras, Titanio, Tratamiento térmico |
| Keyword: | Engineering, Chemical engineering, Control engineering, Microstructures, Titanium, Heat treatment |
| Full text: | Texto completo (Ver HTML) |
