Hot working behaviour of low-cost Ti-3.4Fe bio-implant alloy

卷:126

Article

关键词: HIGH-TEMPERATURE DEFORMATION;    STACKING-FAULT ENERGY;    DYNAMIC RECRYSTALLIZATION;    CONSTITUTIVE-EQUATIONS;    MECHANICAL-PROPERTIES;    TITANIUM-ALLOY;    FLOW BEHAVIOR;    STRAIN RATES;    MICROSTRUCTURE;    COMPRESSION;   

DOI  :  10.1007/s00170-023-11265-9

来源: SCIE

【 摘 要 】

This study investigated the hot workability of an experimental, non-toxic, low-cost Ti-3.4Fe alloy using flow stress analysis, constitutive modelling, processing maps and microstructural examination. Hot compression tests were performed on Ti-3.4Fe alloy samples at different deformation temperatures (750, 800, 850 and 900 degrees C), strain rates (0.05, 0.1, 1 and 10 s(-1)) and a total strain of 0.6. The compression tests were performed using a Gleeble (R) 3500 thermomechanical simulator. The isothermally compressed samples were analysed using a scanning electron microscope to assess the microstructure. An Arrhenius-based model was used to derive the constitutive constants. From the results, the stress exponent and activation energy were 4.91 and 611 kJ.mol(-1) under the steady-state stress condition and 5.32 and 675 kJ.mol(-1) at peak stress. The stress exponents suggested a dislocation climb and glide mechanism controlling deformation. The processing map showed that the optimum conditions to deform Ti-3.4Fe were 850 degrees C at a strain rate of 0.1 s(-1) for both steady-state and peak stresses. The microstructure revealed kinked, rotated and bent lamella at the safe region (850 degrees C at 0.05 s(-1)), confirming the dominance of dynamic recovery as the softening mechanism. Instabilities manifested as cracks and inhomogeneity at 750 degrees C and 1 s(-1) and at 850 degrees C and 10 s(-1).

【 授权许可】

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