Novel 3D coating of bioactive glass and metallic composites

骨科植入物市场一直预计将显示出强劲的增长，特别是在关节重建领域。在医疗保健预算面临严重压力的时候，需要新型髋关节植入物，以提供更好的临床结果质量，但成本相同或更低。种植体被涂覆以帮助种植体骨整合，这些涂层的组成和结构对种植体-骨整合的速度和强度以及临床结果至关重要。目前的涂层是钛（增强强度）和生物活性玻璃（促进骨骼生长）的组合，这两种材料具有非常不同的热性能，因此如果使用传统的涂层工艺，必须分两阶段进行涂层。通过一种新颖的3D打印工艺应用这些材料的能力，可能在一步之内，将改变骨科植入物的设计和制造。它将提供更大的设计自由度，以创建新的功能优化的材料组合和结构，这是传统工艺无法实现的。该项目整合了中小企业从设计到产品供应的端到端运营能力，以及谢菲尔德大学在端到端模拟方面的专业知识。使用一系列由UoS在一系列先前资助的项目中开发的模拟方法（例如IMMPETUS EPSRC拨款，EP/E063497和EP/F023464），水星中心将应用这些方法来设计和模拟新型生物活性玻璃和金属复合材料3D涂层的端到端制造。我们将使用相场建模来模拟AM过程中的熔化、流体动力学、凝固和相变，以优化该应用的工艺条件。我们将使用我们独特的组合有限元/离散元模型来模拟金属和生物玻璃之间的传热，残余应力和相互作用。多尺度建模将用于连接整个制造过程的微观结构和性能。这将扩展到包括新型复合材料在体内的行为。它将提供一种新的增材制造（AM）工艺，将新型互穿3D玻璃和金属复合涂层应用于3D表面，最初用于骨科（髋关节）植入物。该涂层将使设计和制造更小（微创）的植入物具有“大植入物”的性能，具有更好的机械稳定性和更快的与骨融合，从而提高长期临床性能并降低翻修率。这为患者提供了更好的临床结果，并节省了医疗服务费用。设想的增材制造工艺有可能比目前的两阶段沉积更快、成本更低，并且能够通过术前骨骼扫描制造与患者匹配的植入物（可能在患者附近区域）。可转移到其他部门将通过制造太阳能扩散器材料来证明。

The orthopaedic implant market is consistently projected to show strong growth, particularly in the joint reconstructionsector. At a time where healthcare budgets are under severe pressure, there is a need for novel hip implants that deliver abetter quality of clinical outcome, but at the same or reduced cost. Implants are coated to aid implant bone-integration, andthe composition and structure of these coating is critical to the speed and strength of implant-bone integration and hencethe clinical outcome. The current coating is a combination of titanium (for strength) and bioactive glass (to facilitate boneingrowth), materials which have very different thermal properties and therefore must be laid down in two-stages if using aconventional coating process. The ability to apply these materials by a novel 3D printing process, potentially in one-step,will transform design and manufacture of orthopaedic implants. It will provide much greater design freedom to create newfunctionally optimised material combinations and structures not achievable by a conventional process. This projectintegrates the capabilities of SMEs operating end-to-end from design to product supply and the expertise of the Universityof Sheffield in end-to-end simulation. Using a range of simulation methodologies developed by UoS in a series ofpreviously funded programmes (e.g. IMMPETUS EPSRC grants, EP/E063497 and EP/F023464), the Mercury Centre willapply these to design and simulate the end-to-end manufacturing of the novel 3D coating of bioactive glass and metalliccomposites. We will use phase field modelling to simulate the melting, fluid dynamics, solidification and phasetransformations during AM to optimise the process conditions for this application. We will use our unique combined finiteelement/discrete element modelling to simulate the heat transfer, residual stresses and interaction between the metal andbioglass. Multi-scale modelling will be used to link microstructure and properties throughout the manufacturing process.This will extended to include the behaviour of the novel composite in vivo. It will deliver from design to supply a noveladditive manufacturing (AM) process to apply novel interpenetrating 3D glass and metallic composite coatings onto 3Dsurfaces initially for orthopaedic (hip) implants. The coatings will enable design and manufacture of smaller (minimallyinvasive) implants with 'large implant' performance having better mechanical stability and faster integration with bone thusimproving long-term clinical performance and a reduced revision rate. This delivers a significantly better clinical outcomefor patients and savings for the health service. The envisaged AM process has the potential to be faster and lower costthan current two-stage deposition and to enable the manufacture (possibly in near-patient areas) of implants matched tothe patient using pre-operative bone scans. Transferability to other sectors will be demonstrated by the manufacture of asolar diffuser material.