具有高密度平面断层的独立---薄膜的疲劳行为
JungHun Park1, Yuhyun Park1, Sunkun Choi1
1Department of Mechanical Engineering, Korea Advanced Institute of Science and Technology 291, Daehak-ro, Yuseong-gu, Daejeon 34141, Republic of Korea. gdsim@kaist.ac.kr.
Nanoscale
|May 29, 2024
概括
独立的--- (Ni-Mo-W) 薄膜具有特殊的疲劳寿命,由于密集的平面断层,超过100万个循环. 化降低了这种疲劳阻力,表明谷物边界可塑性是故障机制.
科学领域:
- 材料科学 材料科学 材料科学
- 机械工程 机械工程
- 薄膜技术 薄膜技术
背景情况:
- 独立的薄膜对于纳米结构应用至关重要.
- 了解疲劳行为对于材料可靠性至关重要.
- --- (Ni-Mo-W) 合金具有独特的性能.
研究的目的:
- 为了研究独立的Ni-Mo-W薄膜的疲劳行为.
- 为了将微观结构特征与疲劳性能相关联.
- 评估退火对疲劳寿命的影响.
主要方法:
- 循环负荷测试在现存和化Ni-Mo-W薄膜上进行.
- 进行了微观结构性表征 (质地,粒径宽度,平面断层).
- 疲劳寿命以各种古德曼应力幅度进行评估.
主要成果:
- 随着沉积的薄膜显示出显著的疲劳寿命 (>10^6周期在2190MPa).
- 在500°C下24小时火,显著减少了疲劳寿命 (>2x10^5周期在1050MPa).
- 微观结构在后基本保持不变,但疲劳性能下降.
结论:
- 沉积的Ni-Mo-W薄膜中的密集平面断层抑制了疲劳裂的开始,从而导致高疲劳强度.
- 通过回火改变的粒度边界可塑性被认为是主要的疲劳失败机制.
- 在纳米应用中,Ni-Mo-W薄膜显示出有前途的热和机械可靠性.
相关概念视频
Fatigue
181
Fatigue occurs when materials rupture under repeated or fluctuating loads, even at stress levels far below their static breaking strength. It typically results in brittle failure, even for ductile materials. It is a critical consideration in designing machines and structural components subjected to repetitive or varying loads. The nature of these loadings can range from fluctuating loads like unbalanced pump impellers causing vibrations to repeatedly bending a thin steel rod wire back and forth...
181
Yield Criteria for Ductile Materials under Plane Stress
160
In designing structural elements and machine parts using ductile materials, it is crucial to ensure that these components withstand applied stresses without yielding. Yielding is initially determined through a tensile test, which evaluates the material's response to uniaxial stress. However, tensile stress is insufficient when components face biaxial or plane stress conditions This condition requires advanced criteria to predict failure.
The Maximum Shearing Stress Criterion, also known as...
The Maximum Shearing Stress Criterion, also known as...
160


