摘要
采用直接激光沉积法(DLD)制备了工业纯Ti(CP-Ti)与TNTZO合金复合的Ti/TNTZO层状材料,对其微观组织、相组成、力学性能以及体外生物活性进行了分析。结果表明,通过DLD工艺可制备高致密度、无裂纹的Ti/TNTZO层状材料。所制备的层状材料主要由α/α'与β2相组成。层状材料的Ti层由于合金元素扩散及较快的凝固速率使其组织细化,硬度明显升高;TNTZO层因β稳定元素稀释,亚晶界处产生了大量马氏体,硬度增加。单向拉伸实验结果表明,Ti/TNTZO层状梯度材料具有远高于成分材料CP-Ti和TNTZO的拉伸屈服强度与抗拉强度,但界面处产生的大量马氏体导致了材料塑性降低。对Ti/TNTZO层状材料进行模拟体液浸泡,结果显示,Ti/TNTZO层状材料浸泡过程中未产生明显的腐蚀,且可有效诱导磷灰石的形核与长大,在人体植入物领域具有很好的应用前景。
Commercially pure titanium(CP-Ti)is a human-implant metal material commonly used for cardiovascular scaffolds and dental implants in the medical field.This is because CP-Ti has better biocompatibility and corrosion resistance compared to other alloys such as titanium-aluminum-vanadium alloy(Ti-6Al-4V).However,the low strength properties of CP-Ti have limited its wider application(e.g.,load-bearing components).On the contrary,Novelβtitanium alloys possess higher strength and lower elastic modulus,which has led to the consideration of Ti-Nb based alloys for biomedical applications,while also taking into consideration their biocompatibility and other mechanical properties.Recently,laminated metal composites(LMCs)have attracted a lot of attention due to the excellent properties of the constituent alloys.Direct laser deposition(DLD)is an additive manufacturing technology that can be poten-tially used to manufacture LMCs.In this work,the DLD process was used to manufacture Ti/TNTZO LMC,and CP-Ti and TNTZO alloy powders were the raw materials.Subsequently,the microstructure,phase composition,mechanical properties,and in vitro bioactivity of the Ti/TNTZO LMCs were analyzed.The results demonstrated that high-density,crack-free Ti/TNTZO can be fabricated using the DLD process.Ti/TNTZO is mainly composed ofα/α'andβphases.Transmitted Kikuchi diffraction maps showed the presence ofα"martensite,but due to its low content,there were no relevant peaks in the X-ray powder diffraction spectra.The hardness of the Ti region in the Ti/TNTZO increased due to the diffusion of alloy elements and refinement of the structure formed as a result of a faster cooling rate.However,for the TNTZO region,the hardness also increased due to the martensite transformation caused by the dilution ofβ-stabilizing elements compared with the TNTZO manufactured using the DLD process.In comparison with the CP-Ti and TNTZO made using the DLD process,the microstructure of the Ti/TNTZO multilayered materials was significantly different.The microstructure of Ti layers had coarse columnar grains and fineα/α'plates,and there was acicular martensite at the subgrain boundary of the TNTZO layers.As a result of the alloy elements diffusion,transition layer with a size of approximately 50μm was found between the Ti layer and TNTZO layer.The tensile test results also showed that the multilayered materials have high yield strength and ultimate tensile strength.However,the presence of acicular martensite at the interface reduces the plasticity of the materials.Additionally,the Ti/TNTZO multilayered materials showed good ability to induce apatite formation after soaking in simulated body fluid for 14 d.Therefore,the results of this study showed that the Ti/TNTZO multilayered composites fabricated using the DLD process have potential application in the biomedical field.
作者
张婷
李仲杰
许浩
董安平
杜大帆
邢辉
汪东红
孙宝德
ZHANG Ting;LI Zhongjie;XU Hao;DONG Anping;DU Dafan;XING Hui;WANG Donghong;SUN Baode(Shanghai Key Lab of Advanced High-Temperature Materials and Precision Forming,School of Materials Science and Engineering,Shanghai Jiao Tong University,Shanghai 200240,China)
出处
《金属学报》
SCIE
EI
CAS
CSCD
北大核心
2021年第6期757-766,共10页
Acta Metallurgica Sinica
基金
国家自然科学基金项目Nos.51871152、U1760110和51831011。
