1.Effect of magnesium content on microstructure and properties of powder metallurgy Ti-Mg alloy
Jinlong ZHANG ; Jie TAO ; Yueqin WANG ; Xunzhong GUO ; Tao WANG
Chinese Journal of Tissue Engineering Research 2010;14(16):2933-2936
BACKGROUND: High-strength titanium alloy can be prepared bY using powder metallurgy technique, but there are still some problems such as containing toxic elements or high elastic modulus in prepared alloys.OBJECTIVE: A new Ti-Mg alloy with non-toxic and elastic modulus which is close to human bones and strengths satisfy the requirements for human body implants was successfully prepared by means of powder metallurgy technology, and the effects of magnesium content on the microstructure and mechanical properties of Ti-Mg alloy were systematically studied.METHODS: The Mg powder and 17 powder in different mass ratios were prepared by powder metallurgy process to get a new integrated medical Ti-Mg alloy with excellent comprehensive properties. The porosity, fracture surface morphology and phase constituents of samples were observed by optical microscopy, scanning electron microscopy and X-ray diffraction, and the mechanical properties including bending strength, impact toughness and hardness of the alloys were measured,RESULTS AND CONCLUSION: Magnesium mass increasing firstly decreased and then increased admissible strain. When magnesium mass was 10%, admissible strain was 0.97%, which was highly closed to 0.67% of cortical bone. The porosity decreased from 18.3% to 3.8%, the holes became more tact and distributes more uniform, with the increased of mass ratio of magnesium. And with the increased of mass ratio of magnesium, the hardness, bending strength and elastic modulus of alloys with similar pattern of change, there were little changed when the mass fraction of magnesium less than 10%, they decreased significantly and then tended to stable with the continued to increased of magnesium mass fraction. While the admissible strain firstly decreased and then increased, with the increased of the mass fraction of magnesium. When the mass fraction of magnesium was 10%, the hardness, bending strength, impact toughness satisfied the mechanical requirements for human body implants, and the bending strength and admissible strain were close to human bones, which indicated well biomechanical compatibility.