对局部热处理铁中裂纹传播的调查
Ona Lukoševičienė1, Mindaugas Leonavičius1, Vaidas Lukoševičius2
1Department of Applied Mechanics, Faculty of Civil Engineering, Vilnius Gediminas Technical University, 10223 Vilnius, Lithuania.
Materials (Basel, Switzerland)
|January 25, 2025
概括
剩余应力显著影响层状柔性铁元件的循环和静态故障. 热处理引入了这些应力,改变了运输和采矿设备中的裂纹启动,传播和整体材料性能.
科学领域:
- 材料科学 材料科学 材料科学
- 机械工程 机械工程
- 金工业是一种金工业.
背景情况:
- 循环故障是运输和采矿中使用的柔性铁组件的一个关键问题.
- 故障机制受到生产方法和运营压力的影响.
研究的目的:
- 为了研究残余应力的影响循环和静态故障行为层层的柔性铁.
- 分析热处理如何影响应力分布和材料完整性.
主要方法:
- 测试了层层的柔性铁的紧张紧张 (CT) 样本.
- 应用局部热处理来诱导残余应力.
- 实验方法包括用于变形分析的网格方法和对断裂力学进行ASTM合规测试.
- 使用分析方法来确定压力强度因子和故障值.
主要成果:
- 热处理有效地产生了残余应力,导致应力再分配和材料结构的改变.
- 发现残余应力显著影响裂的发起和传播模式.
- 应力强度因子取决于裂深度,层位置和残余应力大小.
结论:
- 剩余应力在层状柔性铁的疲劳和断裂行为中起着至关重要的作用.
- 通过热处理了解和控制剩余应力对于提高要求高的应用中组件可靠性至关重要.
相关概念视频
Microcracking in Concrete
99
Microcracking in concrete refers to the tiny cracks that can form within the material even before any external load is applied. These microcracks typically occur at the interface between the coarse aggregate and the hydrated cement paste, often as a result of differential volume changes prompted by variations in stress-strain behavior, as well as thermal and moisture movement. Initially, these microcracks remain stable and do not grow substantially until the concrete is stressed to about 30...
99
Types of Non-structural Cracks in Concrete
123
Non-structural cracks are primarily of three types: plastic, early-age thermal, and drying shrinkage cracks. Plastic cracks are further classified into plastic shrinkage cracks and plastic settlement cracks.
Plastic shrinkage cracks typically form within hours after the concrete is poured. The concrete's surface dries faster than the bottom, creating tensile stress that the still-plastic concrete cannot withstand, leading to diagonal or randomly patterned cracks on the concrete surface.
Plastic shrinkage cracks typically form within hours after the concrete is poured. The concrete's surface dries faster than the bottom, creating tensile stress that the still-plastic concrete cannot withstand, leading to diagonal or randomly patterned cracks on the concrete surface.
123
Thermal expansion and Thermal stress: Problem Solving
1.1K
San Francisco's Golden Gate Bridge is exposed to temperatures ranging from -15 °C to 40 °C. At its coldest, the main span of the bridge is 1275 m long. Assuming that the bridge is made entirely of steel, what is the change in its length between these temperatures?
To solve the problem, first, identify the known and unknown quantities. The initial length (L) of the bridge is 1275 m, the coefficient of linear expansion (α) for steel is 12 x 10-6/°C, and the change in...
To solve the problem, first, identify the known and unknown quantities. The initial length (L) of the bridge is 1275 m, the coefficient of linear expansion (α) for steel is 12 x 10-6/°C, and the change in...
1.1K
Temperature Dependent Deformation
138
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...
138
Thermal Stress
2.4K
If the temperature of an object is changed while it is prevented from expanding or contracting, the object is subjected to stress. The stress is compressive if the object expands in the absence of constraint and tensile if it contracts. This stress resulting from temperature change is known as thermal stress. It can be quite large and can cause damage. To avoid this stress, engineers may design components so they can expand and contract freely. For instance, on highways, gaps are deliberately...
2.4K
Thermal Strain
603
Thermal strain is a concept that arises when we consider how temperature changes affect structures. Unlike the conventional assumption that structures remain constant under load, real-world scenarios often involve temperature fluctuations that can significantly impact these structures. Consider a homogeneous rod with a uniform cross-section resting freely on a flat horizontal surface. If the rod's temperature increases, the rod elongates. This elongation is proportional to the temperature...
603


