对RZ5合金板的严重塑料变形影响的调查,使用修改的多通道均通道角压力 (ECAP) 技术
Partha Sarathi Sahoo1, Manas Mohan Mahapatra1, Pandu Ranga Vundavilli1
1School of Mechanical Sciences, Indian Institute of Technology Bhubaneswar, Kansapada 752050, India.
Materials (Basel, Switzerland)
|July 29, 2023
概括
均通角压缩 (ECAP) 在合金中显著改进了超细粒度结构. 这一过程提高了拉力,压力强度和硬度,而柔性损失最小,有利于航空航天和建筑.
科学领域:
- 材料科学 材料科学 材料科学
- 金工业是金工业的一个方面.
- 机械工程 机械工程
背景情况:
- 合金具有高强度与重量比,对于航空航天和汽车应用至关重要.
- 颗粒精炼是提高金属材料机械性能的一个关键策略.
- 平等通道角压缩 (ECAP) 是一种用于谷物提炼的严重塑料变形技术.
研究的目的:
- 为了研究多通热ECAP对Mg-RZ5合金板的影响.
- 在ECAP过程中分析微结构演变和相位形成.
- 评估ECAP对机械性能的影响,包括拉伸强度,压力强度和硬度.
主要方法:
- 热ECAP处理Mg-RZ5合金板,使用120°通道角模具.
- 使用光学显微镜和X射线衍射 (XRD) 的微结构分析.
- 在室温下进行拉伸和压力测试,并进行硬度测量.
主要成果:
- 在四次ECAP通过中,从164μm到12μm实现了显著的超细粒度 (UFG) 提炼.
- 观察到MgZn和CeZn3相的形成,有助于性能增强.
- 在四次通过后,室温拉伸强度增加了高达11.56%,压力强度增加了15.64%.
- 硬度增加了高达16.64%,柔性变化微不足道.
结论:
- 具有120°通道角度的多通热ECAP有效地改进了Mg-RZ5合金微结构.
- UFG结构和新形成的相显著增强了机械性能.
- 这种热机械加工方法对需要高强度合金的工业应用具有前景.
相关概念视频
01:21Plastic Behavior
224
A material's elastic behavior is characterized by the disappearance of stress once the load is removed, allowing the material to return to its original state. However, when stress surpasses the yield point, yielding commences, marking the onset of plastic deformation or permanent set. This change from elastic to plastic behavior is influenced by the peak stress value and the duration before the load is removed. An intriguing observation occurs when a specimen is loaded, unloaded, and...
224
01:14Plastic Deformations
110
It is essential to understand how structural members behave under plastic deformation when the bending stress exceeds the material's yield strength. This state of deformation permanently alters the shape of the member, in contrast to the linear elastic behavior observed before yielding. The strain at any point in the member is expressed in terms of maximum strain. Notably, the neutral axis, which coincides with the centroid during elastic bending, shifts away from the centroid under plastic...
110
01:12Temperature Dependent Deformation
171
In a nonhomogeneous rod made up of steel and brass, restrained at both ends and subjected to a temperature change, several steps are involved in calculating the stress and compressive load. Due to the problem's static indeterminacy, one end support is disconnected, allowing the rod to experience the temperature change freely. Next, an unknown force is applied at the free end, triggering deformations in the rod's steel and brass portions. These deformations are then calculated and added...
171
01:20Plastic Deformation in Circular Shafts
208
When materials are subjected to forces that surpass their yield strength, they undergo a process known as plastic deformation. This results in a permanent alteration or strain in their structure. This concept can be specifically applied to circular shafts, where the deformation leads to a change in its shape. The precise evaluation of this plastic deformation requires understanding the stress distribution within the circular shaft, which is achieved by calculating the maximum shearing stress in...
208
01:26Residual Stresses
244
Residual stresses reside in a structure even after removing the original stress inducer. This phenomenon often arises from varied plastic deformations across different parts of a structure. Consider a rod stretched beyond its yield point. It will not regain its original length due to permanent deformation. Even after load removal, the rod does not entirely lose stress because of uneven plastic deformations, resulting in residual stresses. The computation of these stresses in structures is...
244
00:58Plasticity
2.2K
Plasticity is the property where an object loses its elasticity and undergoes irreversible deformation, even after the deformation forces are eliminated. If a material deforms irreversibly without increasing stress or load, then this is called ideal plasticity. For example, when a force is applied to an aluminum rod, it changes its shape, but it does not return to its original shape once the force is removed. Plastic deformation or ductility is thus a permanent deformation or change in the...
2.2K