不同Ca/P比粉末对宽带激光熔覆梯度生物陶瓷涂层组织结构的影响

采用梯度设计思想,利用宽带激光熔覆技术,在TC4合金表面分别熔覆Ca/P为1.4和1.5的CaH-PO4.2H2O+CaCO3混合粉末制备含羟基磷灰石Ca10(PO4)6(OH2),简称HA]、β-磷酸三钙β-Ca3(PO42),简称β-TCP]的度生物陶瓷涂层.采用XRD、SEM等表征手段,研究不同Ca/P粉末配比对生物陶瓷涂层组织结构的影响.研究表明:由于P在激光条件下存在烧损现象,当Ca/P为1.5的粉末经激光熔覆后所生成的陶瓷组织较Ca/P较1.4结晶状态更好.不同Ca/P粉末以及CeO2的添加量对催化合成HA+β-TCP有着深刻的影响.当Ca/P=1.4,CeO2的添加量为0.4wt%时,催化合成HA+β-TCP的数量最多;而当Ca/P=1.5,CeO2的添加量在0.2～0.4wt%范围内,催化合成HA+β-TCP的量最多.

Effects of different Ca/P on microstructure of laser cladding gradient bioceramic coating

In the present paper,the use of the gradient design and the wide-band laser cladding technology,on the surface of the TC4 alloy,the powder of CaHPO4·2H2O+CaCO3 whose Ca/P is 1.4 and 1.5,was mixed to prepare the gradient bioceramic coating with hydroxyapatite Ca10(PO4)6(OH)2(HA),β-tricalcium phosphate β-TCP β-Ca3(PO4)2].With the aid of scanning electron microscope(SEM),X-ray diffraction(XRD) and other analysis,different Ca/P effected on the bioceraic coating microstructure was studied.Result shows:because the phosphor(P) is burned under the condition of the laser,when Ca/P is 1.5,the ceramic structure after laser cladding has better crystalline state than the ratio 1.4 of Ca/P.Different Ca/P powder and CeO2 contents have significant impact on synthesizing HA+β-TCP.When Ca/P is 1.4 and the addition of CeO2 reaches 0.4wt%,the synthesizing HA+β-TCP is the greatest amount;and when Ca/P is 1.5 and the content of CeO2 is between 0.2wt% and 0.4wt%,the synthesizing HA + β-TCP is the greatest amount.