Binderless nano-polycrystalline diamond (NPCD) as cutting material for precision machining cemented carbide

无粘结剂纳米多晶金刚石（NPCD）作为精密加工硬质合金的切削材料

• 批准号: 446389511
• 负责人: Professor Dr.-Ing. Eckart Uhlmann
• 金额: --
• 依托单位: Fachgebiet Werkzeugmaschinen und Fertigungstechnik
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2020
• 资助国家: 德国
• 起止时间: 2019-12-31 至 2022-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/446389511?language=en
• 关键词: Binderless; nano; polycrystalline; diamond; NPCD

Due to the hardness and strength properties as well as the good wear behaviour is tungsten carbide industrially used for punching moulds, injection moulds and cutting tools. Tungsten carbide belongs to the group of hard-brittle materials and is mainly manufactured with undefined cutting edges by grinding processes. The machining with turning- and milling processes is difficult but enables an effective manufacturing and increased geometry complexity. A limiting factor during the manufacturing with geometrical defined cutting edges is increased tool wear.In this investigation a new cutting material nano polycrystalline diamond (NPCD) is used for the cutting of cemented carbide (WC-Co). Due to the material structure NPCD achieves a hardness H comparable to single-crystalline diamond (SCD) without sharing their disadvantages such as anisotropy. In consequence of the diamond particles with particle diameter in a range of 10 nm ≤ dk ≤ 50 nm as well as the absent binder NPCD has an improved wear behaviour and promises a more efficient machining of hard to cut materials.In order to be able to use this cutting material for specific machining of cemented carbide basic knowledge about the cutting behaviour of cemented carbide, the process behaviour of NPCD during the ultra-precision turning and ultra-precision milling process, as well as their interactions needs to be acquired. Therefore, profound knowledge about the wear mechanisms and process variables, such as the surface roughness values resulting from the process and the process forces Fpr, will be acquired. Furthermore, finite element simulations for description of the mechanical interactions between the tool and the workpiece will be developed. In a first funding period about 24 month the basic knowledge with the turning process and the process simulation will be achieved. In the second funding period, which is also calculated about 24 month, the knowledge is transferred on the milling process and at the end fundamental applications for the ultra-precision turning and ultra-precision milling process with NPCD will be defined.

由于硬度和性能强度以及良好的耐磨性能，碳化钨在工业上用于冲压模具、注塑模具和切削工具。碳化钨属于硬脆材料，主要通过磨削制造具有不规则切削刃的材料。使用车削和铣削工艺进行加工很困难，但可以实现有效的制造并增加几何形状复杂性，在使用几何定义的切削刃进行制造期间，限制因素是刀具磨损增加。在这项研究中，一种新的切削材料。纳米多晶金刚石 (NPCD) 用于切削硬质合金 (WC-Co) 由于其材料结构，NPCD 的硬度 H 与单晶金刚石 (SCD) 相当，但没有各向异性等缺点。粒径在 10 nm ≤ dk ≤ 50 nm 范围内的金刚石颗粒以及不含粘合剂的 NPCD 具有改善的磨损行为，并有望提高效率难切削材料的加工。为了能够使用该切削材料进行硬质合金的具体加工，有关硬质合金切削行为的基础知识，NPCD在超精密车削和超精密铣削过程中的工艺行为，以及它们的相互作用，因此，需要获得关于磨损机制和过程变量的深刻知识，例如过程产生的表面粗糙度值和过程力 Fpr 此外，还需要进行有限元模拟。用于描述将在大约 24 个月的第一个资助期内开发刀具和工件之间的机械相互作用，在第二个资助期内（也计算为大约 24 个月）将获得车削工艺和工艺模拟的基础知识。传授有关铣削工艺的知识，最后将定义 NPCD 超精密车削和超精密铣削工艺的基本应用。