Bignon Aurélien, Chevalier Jérôme, Fantozzi Gilbert
National Institute of Applied Sciences, Department of Research into the Metallurgy and Physical Properties of Materials, CNRS Unit 5510, 69621 Villeurbanne, France.
J Biomed Mater Res. 2002;63(5):619-26. doi: 10.1002/jbm.10379.
Decreasing the microscale morphology of synthetic bone substitutes is of primary importance in order to enhance the morphology of the surface of the material, which is directly in contact with osteoconductive cells when it is implanted in bone. The aim of this study was to investigate the influence of ball milling of slurries on the microscale morphology of hydroxyapatite and tricalcium phosphate bone substitutes and the influence on their processing. Ball milling appeared to be a successful method in order to raise the sintering reactivity of the powders, that is, to decrease the sintering temperature and microstructural morphology of the material. However, it was demonstrated that ball milling had a great influence on dispersion, which became very difficult under long milling times because of dissolution of the calcium phosphate powders. Due to dissolution, ionic species were generated in the slurry and interfered with the dispersing agent. Moreover a reprecipitation process occurred simultaneously, and large particles of the most stable phase (HAP) formed. The presence of such large particles generated stress gradients and cracks in the material during the sintering stage.
为了改善合成骨替代物的微观形态，减小其尺寸至关重要，因为当该材料植入骨中时，其表面形态会直接与骨传导细胞接触。本研究旨在探究浆料球磨对羟基磷灰石和磷酸三钙骨替代物微观形态的影响以及对其加工过程的影响。球磨似乎是提高粉末烧结反应性的一种成功方法，即降低材料的烧结温度和微观结构形态。然而，结果表明球磨对分散性有很大影响，由于磷酸钙粉末的溶解，长时间球磨时分散变得非常困难。由于溶解，浆料中会生成离子物种并干扰分散剂。此外，同时会发生再沉淀过程，形成最稳定相（羟基磷灰石）的大颗粒。在烧结阶段，这些大颗粒的存在会在材料中产生应力梯度和裂纹。
