The Zr345Ti35Al33V alloy having good mechanical properties is a potential structural material to apply in the aerospace industry. The microstructure and mechanical properties of Zr345Ti35Al33V alloy during annealing heat treatment were investigated. The specimens annealed from 500 to 800 °C are composed of α and β two phases. No compound is detected in specimens annealed in that temperature range. The microstructure of annealed specimens is characterized as a typical basketweave microstructure. Two microstructural parameters, thickness of plate α phase and relative fraction of β phase, were measured in specimens annealed at various temperatures. The thickness of plate α phase and the relative fraction of β phase increase with the increasing annealing temperature while the specimens anneal from 500 to 700 °C. However, a decreased phenomenon of those microstructural parameters occurs while the specimen anneals at 800 °C. The strength of examined alloy increases from 1306 to 1370 MPa for tensile strength and from 1116 to 1277 MPa for yield strength, inversely, the elongation decreases from 9.5% to 5.8% with the increasing thickness of plate α phase and fraction of β phase in specimens annealed in the range from 500 to 800 °C.

Effects of annealing treatments on microstructure and mechanical properties of the Zr345Ti35Al33V alloy

Structure and mechanical properties of the annealed TZAV-30 alloy

Existing forms and effects of carbon on the surface structure and hardness of ZrTiAlV alloys with various Zr contents

Abstruct The microstructure evolution and mechanical properties response of a TZAV alloy during combined thermomechanical treatments containing hot rolling, cold rolling and subsequent annealing processes are investigated. Stress induced martensitic transformation presents after cold rolling and results in transformation from β to α ″ phase. Few peaks of ω phase were observed in specimens annealed below 650 °C. The microstructure of cold rolled and low temperature annealed specimens are characterized by stretched β grains and fibrous structures. While annealed at 700 °C, the specimen has most of approximate granular α grains. The average aspect ratio of α grains increases as the annealing temperature increases. After annealing at 800 °C, the stretched β grains recrystallize into approximate equiaxed grains. Tensile testing results showed that the deformed specimens have lower strength than annealed specimens. Hardness results showed the similar trend with strength. Otherwise, the relationships between microstructural parameters and mechanical properties are also discussed in this work. Results show that the strength is greatly dependent on thickness of α grains and content of β phase but has little to do with shape parameters of α grians, conversely, the ductility is related to shape parameters but independent of thickness and content.

Microstructure evolution and mechanical properties response of a TZAV alloy during combined thermomechanical treatments

Inhibition of martensitic formation and mechanical properties of the TZ20 alloy during hot rolling

The hot deformation behaviour and microstructural evolution of a near-α titanium alloy (Ti–5·6Al–4·8Sn–2Zr–1Mo–0·35Si–0·7Nd) containing 0·06%C or 0·3%C with bimodal or Widmanstatten starting microstructures were investigated using isothermal compression test at strain rates of 0·01–10 s−1 in the α+β or β regions. In the α+β region, both alloys exhibited continuous flow softening. The globularisation of transformed β structure or the recrystallisation of globular α phase took place, which was more remarkable in the 0·3%C alloy. In the β region, both alloys exhibited steady-state flow behaviour. Dynamic recrystallisation of the β phase occurred in the 0·06%C alloy, while was absent in the 0·3%C alloy. Due to the solution hardening of carbon atoms for the phases and the pinning effect of the carbides on grain boundary, the apparent activation energies of the 0·3%C alloy are higher than those of the 0·06%C alloy in the corresponding α+β or β phase regions.

S Z Zhang

Papers

Effect of carbon on hot deformation behaviour and microstructural evolution of near-α titanium alloy Ti–5·6Al–4·8Sn–2Zr–1Mo–0·35Si–0·7Nd