一项关于304/45双金属复合螺栓疲劳性能和耐腐蚀性的研究
1College of Materials Science and Engineering, Nanjing Tech University, Nanjing 210009, China.
Materials (Basel, Switzerland)
|June 28, 2023
概括
这项研究开发了新的304/45复合螺栓,与传统钢螺栓相比,其表现出优越的疲劳性能和耐腐蚀性. 冷加工增强了强度,而热处理降低了强度,突出了材料加工的影响.
科学领域:
- 材料科学 材料科学 材料科学
- 机械工程 机械工程
- 金工业是金工业的一个方面.
背景情况:
- 复合材料通过结合不同的成分来提供独特的特性.
- 先进的制造工艺对于开发高性能元件至关重要.
- 了解复合材料的机械和腐蚀行为对于工程应用至关重要.
研究的目的:
- 为了研究304/45复合螺栓的微观结构,疲劳性能和耐腐蚀性.
- 评估冷加工和随后的冷却和炼对这些性能的影响.
- 为了比较304/45复合螺栓与304不钢和碳钢螺栓的性能.
主要方法:
- 热工艺生产复合钢棒. 热工艺生产复合钢棒.
- 绘制和线程制以制造复合螺栓.
- 微结构分析,微硬度测试,疲劳测试 (S-N曲线) 和耐腐蚀性评估.
主要成果:
- 冷加工的304/45复合材料 (304/45-CW) 螺栓由于冷变形而表现出高的微硬度 (474 HV).
- 与35K碳钢螺栓相比,304/45-CW螺栓的疲劳寿命 (300MPa的342,600个循环) 显著更高.
- 304/45-CW螺栓的疲劳强度为~240 MPa,在火和钢化 (304/45-QT) 后降至85 MPa,这是由于冷加工强化损失.
- 观察到304/45-CW螺栓具有出色的耐腐蚀性,不受碳扩散的影响.
结论:
- 冷加工是304/45复合螺栓的有效增强机制,提高了疲劳性能并保持了耐腐蚀性.
- 和炼显著降低了这些复合螺栓的疲劳强度.
- 304/45复合螺栓在要求高疲劳强度和耐腐蚀性能的苛刻应用中,是传统钢螺栓的有希望的替代品.
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