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.

硬质量工具是依靠切割，铣削，钻孔和转弯的生产行业的关键。胶结碳化物（WC-CO）是用于切割工具应用的最著名粉末冶金加工材料之一。这是由于与多晶钻石等替代品相比，出色的硬度/耐磨性和韧性以及低成本的结合。但是，在服务过程中（例如，在加工中），复合结构经历了高机械和热载荷的组合，在该组合中，软碳化物颗粒由软钴粘合剂结合，变形直至过度磨损和断裂降低性能和寿命。 WC-CO中的裂纹路径主要遵循低钴浓度下的WC/WC/CO晶粒以及相边界1。虽然WC晶界特征（晶界网络）的特征是不同掺杂的胶结碳纤维2-5的特征，但了解晶界网络在服务过程中的发展以及最终允许沿晶界的裂纹形成。