关于925A钢的疲劳裂纹传播率的实验研究,用于船舶系统
Li Yu1, Wenyong Guo1, Chenghao Cao1
1College of Power Engineering, Naval University of Engineering, Wuhan 430030, China.
Materials (Basel, Switzerland)
|April 27, 2024
概括
925A钢在较低温度下表现出更好的疲劳寿命和更低的裂传播率,满足极地地区的要求到-60°C. 极端寒冷低于-60°C需要专注于防止极地船舶设计中的脆性骨折.
科学领域:
- 材料科学 材料科学 材料科学
- 机械工程 机械工程
- 海军建筑 海军建筑
背景情况:
- 低温疲劳裂传播对于极地船的结构完整性至关重要.
- 925A钢是极地特殊船只轮的关键材料.
- 在零度以下的温度下了解疲劳行为对于安全至关重要.
研究的目的:
- 为了研究925A钢的疲劳裂纹传播率,从室温下降到-60°C.
- 评估925A钢对于极地环境中低温疲劳应用的适用性.
- 分析影响低温疲劳性能的微结构断裂机制.
主要方法:
- 根据中国标准GB/T6398-2017进行的疲劳裂纹传播试验.
- 在各种低温条件下进行的压力强度因子测试.
- 使用微尺度检查来描述裂行为的骨折形态分析.
主要成果:
- 随着温度的降低,925A钢的寿命延长.
- 在特定的应力强度因子范围内,随着温度的下降,疲劳裂传播率降低.
- 在-60°C观察到柔性骨折,表明适合于典型的极地条件.
- 在极端温度低于-60°C的极端温度下,可能发生脆性故障.
结论:
- 925A钢符合正常极地工作温度的低温疲劳要求.
- 对于极端极地条件的疲劳设计必须优先考虑预防冷脆骨折.
- 骨折形态分析提供了对低温微尺度疲劳机制的见解.
- 实验数据为极地船舶设计中增强耐疲劳性和防止冷脆性骨折提供了一个参考.
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
Mechanical Characteristics of Steel
570
The mechanical characteristics of steel are assessed through various tests that evaluate its strength, toughness, and flexibility. These tests include tension, torsion, impact, bending, and hardness assessments, each providing crucial information about steel's suitability for specific applications.
The tension test is fundamental for determining tensile strength. In this test, a steel specimen is stretched using a gripping device until it breaks. The data collected during this test are used...
The tension test is fundamental for determining tensile strength. In this test, a steel specimen is stretched using a gripping device until it breaks. The data collected during this test are used...
570
Fatigue Strength of Concrete
189
Fatigue, in the context of materials science and engineering, refers to the weakening or failure of a material caused by repeatedly applied loads, even if these loads are below the strength limit of the material. Fatigue strength in concrete is a critical property that influences its durability and longevity. Concrete can fail in two ways due to fatigue. Static fatigue or creep rupture occurs under a constant load or one that increases slowly. The other failure mode is due to cyclical or...
189
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
Stress-Strain Diagram - Ductile Materials
708
The stress-strain relationship in ductile materials such as structural steel or aluminium is intricate and progresses through several stages. When a specimen is loaded, it initially exhibits a linear length increase, depicted by a steep straight line on the stress-strain diagram. It indicates the material is elastically deforming and will return to its original shape once unloaded. However, when a critical stress value is reached, plastic deformation begins. This stage sees substantial...
708
Design Consideration
186
Designing a structure involves a series of considerations, primarily the material's ultimate strength, calculated through tests that measure changes under increased force until the material reaches its breaking point or limit. The ultimate load, where the material breaks, is divided by its original cross-sectional area, resulting in the ultimate normal stress or strength. The ultimate shearing stress is another significant factor taken into account.
The factor of safety is another key...
The factor of safety is another key...
186


