医用可降解Zn-3Cu-xMn合金的制备及组织性能研究

Research on Fabrication,Microstructure and Properties of Medical Absorbable Zn-3Cu-xMn Alloys

为了解决Zn基合金作为生物可降解心血管支架时的强度低、塑性差等问题,通过合金化以及热挤压的方法,制备了生物可降解Zn-3Cu-xMn(x表示Mn的质量分数分别为0%,0.5%,1%,1.5%)合金棒材,并研究了合金中Mn含量与其显微组织、力学性能以及降解性能之间的关系。研究结果表明,合金由Zn基体和CuZn5第二相组成,当Mn的质量分数超过1%后,合金中出现MnZn13相。随着合金中Mn的质量分数由0提升至1.5%,合金的屈服强度由138 MPa提升至198 MPa,抗拉强度由231 MPa提升至355 MPa,但其伸长率下降,由96.2%下降至39.0%。同时,合金在体外降解实验中的降解速率由0.13 mm/a提升至0.49 mm/a。

In view of such flaws as low intensity and poor plasticity found in Zn-based alloys used as biodegradable cardiovascular scaffold,biodegradable Zn-3Cu-xMn(x is mass fraction of Mn of 0%,0.5%,1%,1.5%respectively)alloy bars are prepared by alloying and hot extrusion,followed by a research on the relationship between the content of Mn in the alloy and its microstructure,mechanical properties and degradation properties.The results show that the alloy is composed of Zn matrix and CuZn5 second phase;when the content of Mn exceeds 1%,MnZn13 phase appears in the alloy.With the mass fraction of Mn content in the allot increasing from 0 to 1.5%,correspondingly the yield strength of the alloy increases from 138 MPa to 198 MPa,the tensile strength increases from 231 MPa to 355 MPa,while the elongation decreases from 96.2%to 39.0%.Meanwhile,the degradation rate of the alloy increases from 0.13 mm/a to 0.49 mm/a in vitro.