钛合金表面宽带激光熔覆梯度生物陶瓷复合涂层

Gradient bioceremics composite coating produced by wide-band laser cladding on surface of Ti alloy

为了减少激光熔覆过程中基材与生物陶瓷涂层之间的热应力,设计了一种梯度生物陶瓷复合涂层并采用宽带激光熔覆技术在 Ti 6Al 4V合金上制备了梯度生物陶瓷复合涂层,对其组织和显微硬度进行了研究。结果表明:钙和氧元素主要分布在生物陶瓷涂层中;钛和钒元素主要分布在基材和合金化层内;磷元素分布在合金层与陶瓷层中。合金层中基底组织上分布着白色共晶组织和白色颗粒,基底组织主要为 Ti(Al、P、Fe、V)相,白色共晶组织主要为 Fe2Ti4O +AlV3,白色颗粒为结晶析出的 Al3V0.333 Ti0.666;生物陶瓷层中的基底组织为胞状晶,其上分布有灰色相和白色颗粒相,胞状晶主要为 CaO、CaTiO3 和 HA,灰色相为β TCP及 Ca2Ti2O6,白色颗粒相为 TiO2。合金层的最高硬度为1600Hv0.2,生物陶瓷涂层显微硬度最大值约为1300Hv0.2。

In order to eliminate thermal stress between substrate and bioceramics coating during laser cladding, a kind of gradient bioceramics coating is designed. And the gradient bioceramic composite coating on surface of Ti alloy was prepared by using wide-band laser cladding technique. Its microstructure and microhardness was studied. The experimental results indicated that calcium and oxygen mainly distribute in the bioceramic; Titanium and Vanadium mainly distribute in the substrate and alloying layer; Fe distributes in alloying layer. P mainly exists in the bioceramic coating. The matrix phase in the alloying layer was Ti(Al,P,Fe,V) and the white eutectic structure in the alloying layer was mainly comprised of Fe2Ti4O + AlV3, and the white particle phase is Al3V0.333Ti0.666; The matrix phase in bioceramics coating consists of CaO, CaTiO3 and Hydroxyapatite, and the pale particle phase in bioceramics coating is mainly comprised of β-TCP and Ca2Ti2O6, and white particle phase in bioceramic coating is TiO2. The highest hardness value in the alloy layer was nearly 1600 Hv0.2, while the highest hardness value in the bioceramics coating was approximately 1300 Hv0.2.