...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Materials Science and Engineering >Effect of indentation temperature on nickel-titanium indentation-induced two-way shape-memory surfaces
【24h】

Effect of indentation temperature on nickel-titanium indentation-induced two-way shape-memory surfaces

机译：压痕温度对镍钛压痕双向形状记忆表面的影响

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

This study investigated the effect of temperature on indentation-induced one-way and two-way shape memory properties in Ti-50.3 at% Ni alloy. Indentation temperatures ranged from below the martensite finish temperature (M_f) to above the austenite finish temperature (A_f) with the explicit intent of varying the indented phase. Samples used in the study were characterized by differential scanning calorimetry and transmission electron microscopy (TEM). The topographical behavior of the shape memory effect was investigated through Vickers indentation and laser scanning 3D confocal measurements. The magnitudes of deformation recovery associated with the one-way and two-way shape-memory effect (OWSME, TWSME) decreased with increasing indentation temperatures, which is a reflection of the decreasing volume of material experiencing martensitic reorientation during indentation. Indented and subsequently planarized samples exhibited TWSME protrusions when thermally cycled. Laser scanning measurements were used to characterize the height of the protrusions as increasing depths of material were polished away, which provided insight into the overall affected volume beneath the indent. As indentation temperatures increased, both the height of the protrusions, and consequently the polish depth necessary to completely remove the effect, decreased. TEM investigations revealed that directly underneath a nanoindent the microstructure was very fine due to the high-strain deformation; this was contrasted with a much coarser grain size in the undeformed bulk material. Overall these results strongly imply that the deformation recovery associated with the OWSME and TWSME can be maximized by indenting at temperatures at M_f or below because the volume of deformed microstructure beneath the indent is maximized. This finding has important practical value for any potential application that utilizes indentation-induced phase transformation deformation recovery in NiTi.
机译：本研究调查了温度对Ti-50.3 at％Ni合金中压痕诱导的单向和双向形状记忆性能的影响。压痕温度的范围从马氏体终点温度（M_f）以下到奥氏体终点温度（A_f）以上，其明确意图是改变压痕相。通过差示扫描量热法和透射电子显微镜（TEM）对研究中使用的样品进行了表征。通过维氏压痕和激光扫描3D共焦测量研究了形状记忆效应的形貌行为。与单向和双向形状记忆效应（OWSME，TWSME）相关的变形恢复幅度随着压痕温度的升高而降低，这反映了压痕过程中经历马氏体取向的材料体积的减少。压痕和随后平坦化的样品在热循环时显示出TWSME突起。使用激光扫描测量来表征随着深度增加的材料被抛光掉而形成的突起的高度，这有助于洞悉凹痕下方的整体受影响体积。随着压痕温度的增加，突起的高度以及因此完全消除该影响所必需的抛光深度都减小了。 TEM研究表明，由于高应变变形，在纳米压痕正下方的微观结构非常精细。与此形成对比的是未变形的散装材料中的晶粒尺寸大得多。总的来说，这些结果强烈暗示，通过在M_f或更低的温度下压痕，与OWSME和TWSME相关的变形恢复可以最大化，因为压痕下方的变形微结构的体积最大。这一发现对利用NiTi中压痕引起的相变变形恢复的任何潜在应用都具有重要的实用价值。

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