Effect of HIPing time on the properties of TiAl alloys

Abstract

The compacted TiAl alloys were prepared and the effects of HIPing time on their properties were studied. At 1 100 °C, 80 MPa, the density of TiAl alloy reached up to 3.46 g/cm³ after 10 min HIPing. The densities of TiAl alloys did not significantly increase with the time increasing from 10 min to 70 min. Under the experimental conditions, the TiAl alloys obtained is an unstable state alloy, and the effect of HIPing time on the TiAl phase is not significant. The micro-cracks appear in inner of TiAl alloy with the HIPing time increase. At 1 380 °C, after one hour heat treatment, the micro-cracks disappear and the phase changes into stable state and its microstructure changs into lamella.

Keywords

HIPing time / TiAl alloy / properties

References

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