在空洞沉降过程中,微管的内部和外部表面表面粗度的变化
Hayate Sakaguchi1,2, Takuma Kishimoto3, Saki Suematsu4
1Department of Materials Science, Graduate School of Fundamental Science and Engineering, Waseda University, 3-4-1 Okubo, Shinjuku 169-8555, Japan.
Materials (Basel, Switzerland)
|September 14, 2024
概括
空洞沉降降低了不钢管的表面粗度,即使在随后的拉力变形后. 一个标准公式准确地预测了这种粗度,内部表面通常比外部表面粗.
科学领域:
- 材料科学 材料科学 材料科学
- 机械工程 机械工程
- 表面工程是什么?表面工程是什么?
背景情况:
- 表面粗度的演变在金属成型过程中至关重要.
- 了解空洞沉降过程中的表面变化对于制造精密管道至关重要.
- 使用特定尺寸的不钢管 (1.5毫米OD,0.045毫米壁厚).
研究的目的:
- 为了研究不钢管的空洞沉降过程中表面粗度的变化.
- 为了比较空洞沉降下的粗度演变与单轴拉伸变形.
- 评估现有的表面粗度预测公式对空洞沉降的适用性.
主要方法:
- 在没有内部工具的情况下使用拉杆进行空洞沉降实验.
- 在起始材料上进行了单轴拉伸试验.
- 在模具入口和出口点测量和比较内部和外部表面的表面粗度.
主要成果:
- 单轴拉伸变形增加了表面粗度,特别是在模具入口.
- 空洞沉降显著降低了表面粗度,这种降低在进一步的拉伸变形后仍然存在.
- 内部表面粗度始终高于外部表面粗度.
- 预测金属板表面粗度的常规公式也准确地预测了空洞沉降中的管道粗度.
结论:
- 空洞沉有效地通过平滑外表面来抑制表面粗度的增加.
- 内表面粗度倾向于增加,因为死后的变形,死后退出模具.
- 该研究验证了使用既定公式来预测空洞沉降过程中的表面粗度.
相关概念视频
01:13Excess Pressure Inside a Drop and a Bubble
The shape of a small drop of liquid can be considered spherical, neglecting the effect of gravity. This drop can further be considered as two equal hemispherical drops put together due to surface tension. The forces acting on the spherical drop are due to the pressure of the liquid inside the drop, the pressure due to air outside the drop, and the force due to the surface tension acting on the two hemispherical drops.
01:25Minor Losses in Pipes
In pipe systems, minor losses refer to energy losses arising from components such as valves, bends, fittings, expansions, and other features that disrupt the steady flow of fluid. These disturbances cause energy dissipation through turbulence and resistance, which engineers quantify to manage system efficiency effectively.
Valves play a significant role in generating minor losses by obstructing or redirecting the fluid flow. When a valve is closed or partially closed, it restricts the flow...
Valves play a significant role in generating minor losses by obstructing or redirecting the fluid flow. When a valve is closed or partially closed, it restricts the flow...