In-service Catastrophic Failure: or Controlling the Grain Boundary Network Evolution

运行中的灾难性故障：或控制晶界网络的演化

• 批准号: 2888456
• 金额: --
• 依托单位: Imperial College London
• 依托单位国家: 英国
• 项目类别: Studentship
• 财政年份: 2023
• 资助国家: 英国
• 起止时间: 2023 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=studentship-2888456
• 关键词: service; Catastrophic; Failure; Controlling; Grain

Hardmetal tools are a key for our production industries relying on cutting, milling, drilling, and turning. Cemented carbides (WC-Co) are one of the most prominent powder metallurgy processed materials use for cutting tool applications. This is due to a combination of excellent hardness/wear resistance and toughness with low cost compared to alternatives such as polycrystalline diamond. During service (e.g. in machining) , however, the composite structure is subjected to a combination of high mechanical and thermal loads, where hard carbide particles are joint by soft cobalt binder, deforms until excessive wear and fracture reduce the performance and lifetime. Crack paths in WC-Co predominantly follow WC/WC and WC/Co grain and phase boundaries at low cobalt concentrations1. While the WC grain boundary character, the grain boundary network, is characterised for differently doped cemented carbides2-5, knowledge of how the grain boundary network evolves during service and ultimately allows for crack formation along grain boundaries is absent.

硬质合金工具是我们依赖切削、铣削、钻削和车削的生产行业的关键。硬质合金（WC-Co）是用于切削刀具应用的最突出的粉末冶金加工材料之一。这是由于与多晶金刚石等替代品相比，具有优异的硬度/耐磨性和韧性以及低成本。然而，在使用期间（例如，在机加工中），复合结构经受高机械和热负荷的组合，其中硬质碳化物颗粒通过软钴粘结剂接合，变形直到过度磨损和断裂降低性能和寿命。在低钴浓度下，WC-Co中的裂纹路径主要沿着WC/WC和WC/Co晶界和相界1。虽然WC晶界特征、晶界网络是以不同掺杂的硬质合金2 -5为特征的，但是缺乏关于晶界网络在使用期间如何演变以及最终允许沿着晶界形成裂纹的知识。