Fracture initiation in FCC and BCC metals during tribology

摩擦过程中 FCC 和 BCC 金属的断裂萌生

• 批准号: 324591046
• 负责人: Privatdozent Dr. Steffen Brinckmann
• 金额: --
• 依托单位: IEK-2: Werkstoffstruktur und -eigenschaften
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2016
• 资助国家: 德国
• 起止时间: 2015-12-31 至 2020-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/324591046?language=en
• 关键词: Fracture; initiation; FCC; BCC; metals

According to the current scientific understanding of wear of metals, the crack initiation mechanism is linked to surface fatigue, which occurs as the metal experiences repeated loading cycles. However, my preliminary fundamental experiments using a microasperity reveal that cracks can develop even during the first friction stroke. Moreover, I observed that the crack evolution is grain orientation dependent: while cracks develop in one grain, another grain is crack free although both grains experience the same loading. This project investigates the basic mechanisms of crack growth and the interaction of micro-cracks and micro-plasticity in unlubricated contacts of an engineering FCC steel and a corresponding BCC model-alloy. Using micrometer experiments with auxiliary simulations, I will determine grain orientation dependent crack formation, the crack growth rate and subsequent loading. With the fundamental understanding of crack initiation due to a single microasperity, one can acquire a better understanding of macroscale tribology, which is the combined contact and interaction of a multitude of microasperities. This improved macroscale understanding can result in a reduction of wear and friction and, hence, in a reduction of replacement costs, noise and energy consumption.

根据目前对金属磨损的科学认识，裂纹萌生机制与表面疲劳有关，表面疲劳是在金属经历重复的载荷循环时发生的。然而，我使用微粗糙体进行的初步基础实验表明，即使在第一次摩擦行程期间也会出现裂纹。此外，我观察到裂纹的演变取决于晶粒取向：当一个晶粒中出现裂纹时，另一种晶粒则没有裂纹，尽管两个晶粒承受相同的载荷。该项目研究了工程 FCC 钢和相应的 BCC 模型合金的未润滑接触中裂纹扩展的基本机制以及微裂纹和微塑性的相互作用。使用微米实验和辅助模拟，我将确定与晶粒取向相关的裂纹形成、裂纹扩展速率和随后的载荷。通过对单个微粗糙体引起的裂纹萌生的基本了解，人们可以更好地理解宏观摩擦学，即多个微粗糙体的组合接触和相互作用。这种改进的宏观理解可以减少磨损和摩擦，从而减少更换成本、噪音和能源消耗。

项目成果

Insight into indentation-induced plastic flow in austenitic stainless steel

• DOI: 10.1007/s10853-020-04646-y
• 发表时间: 2020-04
• 期刊: Journal of Materials Science
• 影响因子: 4.5
• 作者: Wenzhen Xia;G. Dehm;S. Brinckmann

On the commensuration of plastic plowing at the microscale

论微观尺度塑耕的可比性

• DOI: 10.1016/j.triboint.2020.106477
• 发表时间: 2020
• 期刊: Tribology International
• 影响因子: 6.2
• 作者: Tsybenko;Brinckmann
• 通讯作者: Brinckmann

Unraveling indentation-induced slip steps in austenitic stainless steel

• DOI: 10.1016/j.matdes.2019.108169
• 发表时间: 2019-12
• 期刊: Materials & Design
• 影响因子: 8.4
• 作者: Wenzhen Xia;G. Dehm;S. Brinckmann

Investigation of single asperity wear at the microscale in an austenitic steel

• DOI: 10.1016/j.wear.2020.203289
• 发表时间: 2020-07
• 期刊: Wear
• 影响因子: 5
• 作者: Wenzhen Xia;G. Dehm;S. Brinckmann