• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文会议>Fatigue and fracture mechanics >An Examination of Fatigue Initiation Mechanisms in Thin 35Co-35Ni-20Cr-10Mo Medical Grade Wires
【24h】

An Examination of Fatigue Initiation Mechanisms in Thin 35Co-35Ni-20Cr-10Mo Medical Grade Wires

机译：35Co-35Ni-20Cr-10Mo医用级细钢丝疲劳起爆机理的研究

获取原文
获取原文并翻译 | 示例
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Knowledge of the intrinsic defect size distribution, surface grain size distribution, and prior deformation history are important factors in determining fatigue crack initiation mechanisms and total life variability in thin, metallic, medical grade wires. The ASTM F562 alloy system is used extensively as a fine wire coil or cable in the production of cardiac rhythm management leads which require excellent fatigue life, and a good understanding of life variability. In the present investigation, samples of 0.0070 in. diameter ASTM F562, 35Co-35Ni-20Cr-10Mo wires were produced with a variety of grain sizes and strain hardening conditions. Samples were then cyclically loaded to failure in rotary beam testing and preserved for post mortem frac-tography using high resolution scanning electron microscopy (HR-SEM). Fatigue cracks were found to initiate from three sources: intrinsic microstruc-tural inhomogeneities, persistent slip bands (PSBs), and extrinsic surface defects. The dominance of the various initiation mechanisms was shown to be a function of the constituent particle and grain size as well as the fatigue loading conditions and prior deformation history. In samples exhibiting a surface grain size significantly larger than the constitutive particle distribution, cracks were observed to preferentially nucleate from surface intersecting PSBs rather than near-surface-particles. Understanding of these phenomena is important in the design of robust cardiac lead systems that will outlive the patient.
机译：固有缺陷尺寸分布，表面晶粒尺寸分布和先前的变形历史的知识是确定疲劳裂纹萌生机理和细，金属，医用级电线总寿命变化的重要因素。 ASTM F562合金系统广泛用于生产心律管理导线的细线圈或电缆，这些导线需要出色的疲劳寿命，并对寿命可变性有很好的了解。在本研究中，使用各种晶粒尺寸和应变硬化条件生产了直径为0.0070英寸ASTM F562、35Co-35Ni-20Cr-10Mo线材的样品。然后将样品循环加载到旋转束测试中失败，并使用高分辨率扫描电子显微镜（HR-SEM）进行尸检后保存。发现疲劳裂纹是从三个来源引发的：固有的微观结构不均匀性，持续的滑移带（PSB）和外部的表面缺陷。结果表明，各种引发机制的主导地位与组成颗粒和晶粒大小，疲劳载荷条件和先前的变形历史有关。在表现出明显大于本构颗粒分布的表面晶粒尺寸的样品中，观察到裂纹优先从相交的表面PSB而不是近表面颗粒成核。对这些现象的理解对于设计耐用的心脏导联系统非常重要，该系统将使患者寿命更长。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号