Cailiao gongcheng (Oct 2024)
Effect of heat treatment on microstructures and properties of Zr-rich α TiZrAl alloy
Abstract
The microstructures and properties of two kinds of zirconium-enriched α alloys (Ti60Zr40)97Al3(mass fraction/%,the same below) and (Ti50Zr50)97Al3 via different heat treatments were investigated and analyzed based on optical microscope (OM) observation, differential scanning calorimetric (DSC) measurement, X-ray diffraction (XRD) measurement, scanning electron microscope (SEM) observation and tensile tests at room temperature.The results show that after 850 ℃/40 min annealing, microstructures consisting of basket-weave α phase and a small amount of reticular β phase are formed in the alloys. After 850 ℃/40 min quenching, the acicular α' martensite phase is formed. After 850 ℃/40 min quenching and then 600 ℃/4 h aging, a large part of α' martensite phase converts into α phase, and the microstructures of the alloys consist of α and α'remain phases. The yield strength of the T40Z3A alloy can reach 1100 MPa, with a favourable tensile elongation of 7%. The T50Z3A alloy exhibits higher strength but lower ductility than those of the T50Z3A alloy. Due to the higher content of Zr element, the T50Z3A alloy has more reticular β phase after annealing and more remaining α' martensite phase after quenching and aging, which results in higher strength and lower ductility.
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