| Laser rapid prototyping technology is an advanced manufacturing technology, using the laser melting deposition to directly fabricate physical objects with complicated structure and shape on the basis of virtual 3D model data. With the advantages, such as high flexibility, short cycle of laser rapid prototyping technology, this technology have great potential in the field of modern biomedical materials manufacturing. Currently, biomedical materials for LRP are based on traditional alloy at home and abroad. However, some researches show that the traditional biomedical materials are still unable to meet the requirements of laser rapid forming process, such as good liquid flow ability, deoxidizing and low segregation properties.In this paper, set the aim as low modulus of elasticity, good deoxidizing and biological compatibility, Sn and Y with were added as components to the biomedical Ti-Fe-Sn-Y alloy system based on the Ti-Fe eutectic alloy through "cluster-plus-glue-atom" model. Additionaly, the Ti-Fe-Sn-Y alloy was deposited on pure titanium substrate by laser rapid prototyping technology. The microstructure and phases of Ti-Fe-Sn-Y alloy and Ti70.58Fe29.42 were identified by X-ray diffraction (XRD), scanning electron microscopy (SEM). The relationship between alloy elements and microstructure, surface rough degree, density, hardness, Young’s modulus and corrosion resistance of the alloy were investigated by 3D profilometer, density tester, micro-hardness tester, nano indenter, friction wear tester and electrochemical work station. Comparative analysis with Ti70.58Fe29.42 binary eutectic alloy was also made.The results show that, the element Y purifys liquid phase and suppresses the formation of Ti4Fe2O oxide. The formation of Ti-Fe-Sn-Y alloy is mainly composed of (3-Ti solid solution and TiFe intermetalic compound. With the increaseing Sn,a small amount of TisSn phase precititated. During the laser rapid forming process of non-equilibrium solidification, the microstructure of the Ti-Fe-Sn-Y alloys changes from hypereutectic structures to the hypoeutectic structures with the increasing Sn content due to asymmetry pseudo-eutectic zone tends is skewed to the high melting point phase β-Ti).When the Sn content is 4.40 at.%,the composition is very close to eutectic point,which forms a near eutectic structure.With the increaseing Sn,the alloy Ti-Fe-Sn-Y’s surface roughness decreases first and then increases. The surface roughness reaches the lowest point when Sn content addition amount is 4.40 at.%, which is superior than Ti70.58Fe29.42 binary eutectic alloy. With Sn addition increased, the density gradually increases and hardness gradually decreases, and elastic modulus decreases and then increases. When Sn content addition to 5.86 at.%, it reaches the minimum value and decreases by 35% compared with the Ti70.58Fe29.42. Friction and wear experimental results show that, main wear mechanism of the alloy is adhesive wear and abrasive wear. With increase of Sn content, friction coefficient of the Ti-Fe-Sn-Y first decreases and then increases, which reaches the lowest point when the Sn content is 5.86 at.%. The optimal antifriction is also obtained when the Sn content is 5.86 at.%. The wear volume decreases gradually while wear resistance of the alloy increased gradually. Electrochemical experiments show that with increaseing Sn content, the alloy Ti-Fe-Sn-Y into form in Hank’s solution resistance corrosion resistance decreased gradually, but generally superior to Ti70.5gFe29.42 binary eutectic alloy when applied to the corrosion resistance in the human’s body. |
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