STTR Phase I: Mechanical Surface Treatment for High Performance Biodegradable Implants

STTR 第一阶段：高性能可生物降解植入物的机械表面处理

• 批准号: 1521188
• 负责人: Michael Sealy
• 金额: $ 22.5万
• 依托单位: Surface Integrity, LLC
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-07-01 至 2016-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1521188&HistoricalAwards=false
• 关键词: STTR; Phase; Mechanical; Surface; Treatment

The broader impact/commercial potential of this Small Business Technology Transfer (STTR) Phase I project is to shift current practices in bone fracture fixation care from using permanent metal implants to biodegradable metal implants (screws, plates, pins, rods, etc.). A promising biodegradable metal that is gaining widespread attention is magnesium. This project will advance magnesium implant technology towards becoming a viable alternative biomaterial for fracture fixation care. A magnesium implant?s biodegradation can be customized to an individual patient or application by modifying surface properties of an implant through surface treatments. If successful, patients will no longer have to rely on off-the-shelf permanent implants for treating bone fractures or require secondary removal surgeries to prevent the long-term complications with these devices. A senior patient with osteoporosis can have an implant that degrades slowly since his/her bones heal slowly, while a younger patient can have an implant that degrades quickly since his/her bones heal quickly. The commercial impact will be an unprecedented shift in the orthopedic industry towards customizable healthcare. The use of biodegradable metal implants will not only improve the quality of life of the affected individuals but also boost the competitiveness of the US medical device industry.The proposed project will demonstrate the feasibility of using surface treatments, such as laser shock peening or burnishing, on the surface of a magnesium implant to control the biodegradation while maintaining necessary mechanical integrity. Permanent metal implants made of titanium or stainless steel have unsatisfactory performance such as stress shielding. In addition, they are often removed with a secondary surgery after the bone heals. An alternative biodegradable material is needed that avoids the complications inherent to permanent metals. Magnesium is a promising biodegradable metal. The critical issue that hinders the adoption of this material for orthopedic applications is its high corrosion rate in the human body. Surface treatments are an effective method to slow the corrosion rate. The research objectives are to (1) create a surface layer on a magnesium alloy that degrades in 3 weeks to 3 months while maintaining structural integrity and (2) develop a model that designs a surface treatment procedure to meet the degradation and structural integrity needs of a patient. These objectives will be accomplished by (a) determining corrosion rate and mechanical degradation rate over time for different surface treatments and (b) understanding the relationships between surface treatment, surface integrity, and performance.

该小型企业技术转让（STTR）I期项目的更广泛影响/商业潜力是将骨折固定护理的当前实践从使用永久性金属植入物转变为可生物降解的金属植入物（螺钉、接骨板、骨针、棒等）。镁是一种很有前途的可生物降解的金属，正受到广泛关注。该项目将推进镁植入物技术，使其成为骨折固定护理的可行替代生物材料。镁植入物？通过表面处理改变植入物的表面性质，可以针对个体患者或应用定制生物降解。如果成功的话，患者将不再需要依赖现成的永久性植入物来治疗骨折，或者需要二次取出手术来防止这些器械的长期并发症。患有骨质疏松症的老年患者可以具有缓慢降解的植入物，因为他/她的骨骼愈合缓慢，而年轻患者可以具有快速降解的植入物，因为他/她的骨骼愈合迅速。商业影响将是骨科行业向可定制医疗保健的前所未有的转变。使用可生物降解的金属植入物不仅可以改善患者的生活质量，还可以提高美国医疗器械行业的竞争力。拟议项目将证明在镁植入物表面使用表面处理（如激光冲击喷丸或抛光）的可行性，以控制生物降解，同时保持必要的机械完整性。由钛或不锈钢制成的永久性金属植入物具有不令人满意的性能，例如应力屏蔽。此外，它们通常在骨愈合后通过二次手术移除。需要一种替代的可生物降解材料，以避免永久性金属固有的并发症。镁是一种很有前途的可生物降解金属。阻碍这种材料用于骨科应用的关键问题是其在人体内的高腐蚀率。表面处理是减缓腐蚀速率的有效方法。研究目标是（1）在镁合金上创建一个表面层，在3周至3个月内降解，同时保持结构完整性;（2）开发一个模型，设计一个表面处理程序，以满足患者的降解和结构完整性需求。这些目标将通过（a）确定不同表面处理随时间的腐蚀速率和机械降解速率以及（B）了解表面处理、表面完整性和性能之间的关系来实现。

项目成果

Modeling thermal and mechanical cancellation of residual stress from hybrid additive manufacturing by laser peening

通过激光喷丸对混合增材制造残余应力的热和机械消除进行建模

• DOI: 10.1016/j.npe.2019.07.001
• 发表时间: 2019
• 期刊: Nanotechnology and Precision Engineering
• 作者: Madireddy, Guru;Li, Chao;Liu, Jingfu;Sealy, Michael P.
• 通讯作者: Sealy, Michael P.