结合商业纯度的严重塑料变形加工,为下一代植入物提供了卓越的疲劳耐受性
Alexander Kopp1, Jonas Werner2, Nadja Kröger3
1Meotec GmbH, Aachen 52068, Germany.
Biomaterials advances
|January 11, 2024
概括
使用ECAP/RS加工的商业纯度 (cp-Ti) 显示出优越的强度和耐疲劳性,可能会在医疗植入物中取代Ti64. 这种先进的cp-Ti保持了生物相容性和耐腐蚀性,用于更安全,更小的医疗器械.
科学领域:
- 生物材料工程 生物材料工程
- 材料科学 材料科学 材料科学
- 整形外科植入物 整形外科植入物
背景情况:
- 商业纯度 (cp-Ti) 是Ti64的潜在替代品,因为人们担心和离子的毒性.
- 然而,cp-Ti的机械性能,特别是耐疲劳性,对于植入物应用是不够的.
- Ti64是一种常见的合金,用于医疗植入物.
研究的目的:
- 通过先进的加工技术,提高cp-Ti等级4的机械性能.
- 评估产生的材料是否适合作为医疗植入物中Ti64的替代品.
- 研究强化机制,评估生物相容性和耐腐蚀性.
主要方法:
- 使用等通道角压和旋转交换 (ECAP/RS) 处理cp-Ti等级4杆.
- 进行拉力和疲劳测试以评估机械性能.
- 使用显微镜进行微观结构分析,并评估耐腐蚀性和生物相容性.
主要成果:
- 实现了1383 MPa的平均承受强度,具有10%的柔性,超过了Ti64.
- 增加了43%的疲劳耐力极限,达到600MPa,接近Ti64的性能.
- 超细粒度 (UFG) 微观结构,晶体纹理和亚粒度结构被确定为增强机制.
- 耐腐蚀性和生物相容性基本上没有受到影响.
结论:
- 结合ECAP/RS处理显著提高cp-Ti等级4的强度和耐疲劳性.
- 经过加工的UFG cp-Ti等级4显示出替代Ti64的潜力,并使植入物缩小.
- 这种材料为医疗器械提供了一个有前途的替代品,保持了医疗器械的生物相容性和耐腐蚀性.
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