STTR Phase II: Cold Gas Dynamic Spray Processing of Bioactive Nano-hydroxyapatite/Titanium Nanocomposite Coatings

这个小型企业技术转移（STTR）第二阶段项目将开发一种完全集成的工艺，通过新型冷气体动态喷雾（CGDS）或超动能沉积工艺，将粘合良好的生物活性涂层应用于骨科髋关节植入物的茎部。新工艺是医疗植入物表面修饰技术的一个潜在的重大进步。迄今为止，医学界主要依靠等离子喷涂来激活植入物表面。等离子喷涂是一种经济有效的涂覆方法，但效果并不理想。特别是羟基磷灰石饲料粉末在等离子喷涂过程中所经历的高温会严重降低其成分的完整性，从而影响其生物活性。冷喷雾工艺消除了这一问题，并首次使高表面积纳米结构羟基磷灰石粉末融入植入物表面，而不牺牲其固有的生物活性。作为一个额外的好处，种植体表面处于压缩状态，这应该通过消除低周疲劳引起的表面开裂的可能性来延长种植体的使用寿命。该项目的商业应用将是提高植入物的寿命。

This Small Business Technology Transfer (STTR) Phase II Project will develop a fully integrated process for applying a well-bonded, bioactive coating to the stem of an orthopedic hip implant by a novel Cold Gas Dynamic Spray (CGDS), or Hyperkinetic Deposition process. The new process is a potential major advance in the state-of-the-art for surface modification of medical implants. The medical community hitherto has relied primarily on plasma spraying to activate implant surfaces. Plasma spraying is a cost-effective means of applying the coating material but is far from ideal. In particular, the high temperatures experienced by the hydroxyapatite feed powder during plasma spraying can seriously degrade its compositional integrity and thus its bioactive properties. The cold spray process eliminates this problem, and enables, for the first time, high-surface-area nanostructured hydroxyapatite powder to be incorporated into the implant surface withoutsacrificing its intrinsic bioactivity. As an added benefit the implant surface is left in a state of compression, which should extend the service life of the implant by eliminating the possibility of surface cracking caused by low-cycle fatigue.The commercial applications for this project will be to improve the life of implants.