Tungsten is commonly used in cemented carbide tooling solutions and as an alloying element in superalloys and steels. In pure form, as a single-phase tungsten, it is used in nuclear and research facilities. Tungsten is known for its poor machinability resulting in excessive tool wear, which puts high requirements on the selected tooling solution. Also, single-phase tungsten is a highly brittle material, thus often leading to surface damage when machining. In this study, eleven different tool materials: ceramics, coated and uncoated cemented carbide, cermet, PcBN and PCD have been tested in longitudinal turning of high purity tungsten (W > 99.9%) in order to identify suitable tool candidates. Seven cutting tool solutions consistently suffered from excessive tool wear or breakage after a few seconds of engagement time. Only two tool materials, PCD and PVD (TiAlN – TiSiN) coated cemented carbide provided sufficient performance. Analysis of their wear mechanisms with scanning and transmission electron microscopy revealed abrasion, oxidation and cracking of WC grains and diffusional dissolution of WC and Co in case of carbide tools. For PCD tools the main identified mechanisms are abrasion and diffusional dissolution. Cracking, formation of build-up edges, presence of workpiece porosity and W adhesion on the machined surface was found to be responsible for poor surface quality and sub-surface damage. Surface roughness for the PCD ranged within R_a = 1.3–1.7 μm and for the PVD coated carbide tool R_a = 1.0–1.5 μm.

钨通常用于硬质合金刀具解决方案中，并用作高温合金和钢中的合金元素。纯形式的钨是单相钨，用于核设施和研究设施。钨因其可加工性差而导致工具过度磨损而著称，这对选定的工具解决方案提出了很高的要求。同样，单相钨是一种高脆性材料，因此在加工时经常导致表面损坏。在这项研究中，已经在高纯度钨（W> 99.9％）的纵向车削中测试了11种不同的刀具材料：陶瓷，涂层和未涂层​​的硬质合金，金属陶瓷，PcBN和PCD，以确定合适的候选刀具。啮合几秒钟后，七个切削刀具解决方案始终遭受过度的刀具磨损或损坏。只有两种工具材料 PCD和PVD（TiAlN – TiSiN）涂层硬质合金具有足够的性能。用扫描和透射电子显微镜对它们的磨损机理进行分析后发现，在使用硬质合金刀具的情况下，WC晶粒的磨损，氧化和破裂以及WC和Co的扩散溶解。对于PCD工具，主要确定的机理是磨损和扩散溶解。发现开裂，堆积边缘的形成，工件孔隙的存在和机加工表面上的W附着力是造成不良表面质量和次表面损坏的原因。PCD的表面粗糙度在 在使用硬质合金刀具的情况下，WC晶粒的氧化和破裂以及WC和Co的扩散溶解。对于PCD工具，主要确定的机理是磨损和扩散溶解。发现开裂，堆积边缘的形成，工件孔隙的存在和机加工表面上的W附着力是造成不良表面质量和次表面损坏的原因。PCD的表面粗糙度在 在使用硬质合金刀具的情况下，WC晶粒的氧化和破裂以及WC和Co的扩散溶解。对于PCD工具，主要确定的机理是磨损和扩散溶解。发现开裂，堆积边缘的形成，工件孔隙的存在以及机加工表面上的W附着力是造成不良表面质量和次表面损坏的原因。PCD的表面粗糙度在R _a  = 1.3–1.7μm，对于PVD涂层硬质合金刀具，R _a  = 1.0–1.5μm。