Martensite strengthening of titanium alloys

Journal Article · Tue Dec 31 23:00:00 EST 1974 · Met. Sci. Heat Treat. (USSR) (Eng. Transl.); (United States)

DOI:https://doi.org/10.1007/BF00664318· OSTI ID:7361730

Moiseev, V N; Polyak, E V; Sokolova, A Yu

The effect of ..cap alpha..' and ..cap alpha..'' phases on the mechanical properties of commercial titanium alloys of the martensite type (VT6, VT14, VT3-1, VT16) was investigated. A substantial strengthening effect (as much as 30 percent) in alloys VT6, VT14, and VT3-1 is due to the formation of ..cap alpha..' phase in quenching. The best combination of strength and ductility was found for alloys of the martensite type quenched from temperatures in the ..cap alpha.. + ..beta.. region near the end of the ..cap alpha.. + ..beta.. ..-->.. ..beta.. transformation. The effect of Mo, V, Fe, Cr, and Mn concentrations on the properties of titanium martensite (..cap alpha..') was investigated. It was found that increasing the amount of ..beta.. stabilizer in the ..cap alpha..' phase increases its strength, lowering the ductility. The largest increase in strength was observed in alloys with the highest supersaturation of ..cap alpha..' phase with the ..beta.. stabilizing element. With increasing transformation of ..cap alpha..' to ..cap alpha..'' phase in quenched Ti--Mo and Ti--V alloys the strength decreases gradually. The addition of aluminum to titanium alloys with ..beta.. stabilizing elements leads to an increase in the strength of ..cap alpha..' phase and a larger increase of the strength after quenching. Transmission electron microscopy revealed changes in the fine structure of metastable ..cap alpha..' martensite with increasing amounts of ..beta.. stabilizers. With 1 to 4 percent Mo the number of regions with twins decreases; the number of ..cap alpha..' needles with a high dislocation density increases, and also the number of orientations. With 5 to 9 percent Mo the number of ..cap alpha..' needles decreases and the number of ..cap alpha..'' plates increases, more even orientation of the plates, and a lower dislocation density than ..cap alpha..' phase.

• OSTI ID: 7361730
• Journal Information: Met. Sci. Heat Treat. (USSR) (Eng. Transl.); (United States), Journal Name: Met. Sci. Heat Treat. (USSR) (Eng. Transl.); (United States) Vol. 17:7/8; ISSN MHTRA
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360103* -- Metals & Alloys-- Mechanical Properties
ALLOY-VT14
ALLOY-VT16
ALLOY-VT6
ALLOYS
ALUMINIUM ADDITIONS
ALUMINIUM ALLOYS
CHEMICAL COMPOSITION
HEAT TREATMENTS
IRON ADDITIONS
IRON ALLOYS
MECHANICAL PROPERTIES
MOLYBDENUM ALLOYS
PHASE TRANSFORMATIONS
QUENCHING
SILICON ADDITIONS
SILICON ALLOYS
TITANIUM ALLOYS
TITANIUM BASE ALLOYS
VANADIUM ADDITIONS
VANADIUM ALLOYS
YIELD STRENGTH