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Ultrafine tungsten carbide (WC)–cobalt (Co) and WC–(Ti,W)C–Co end mills were produced via spark plasma sintering. The wear mechanism of these end mills during machining of AISI H13 steel was investigated. WC–Co exhibits good mechanical properties (HV30: 2110 kg/mm2, KIC: 10.4 MPa/m1/2, TRS: 1990 MPa). Although the high hardness of WC–Co makes it show excellent resistance to abrasive wear, it suffers from a significant adhesion problem. As the cutting temperature increases, the oxidation of the WC–Co causes damage to the microstructure of tool materials, which deteriorates the grain boundary strength and promotes adhesive wear. This phenomenon causes large areas of tool materials to chip off and eventually results in cutting‐edge breakage. The high brittleness of (Ti,W)C causes cracks to propagate at low‐stress levels, reducing the mechanical properties of WC–(Ti,W)C–Co (KIC: 8.8 MPa/m1/2, TRS: 1090 MPa). However, (Ti,W)C addition enhances the resistance to oxidation and workpiece adhesion, which reduces the tool material loss caused by adhesive wear. The tool life of WC–(Ti,W)C–Co is three times longer than that of WC–Co in milling of AISI H13 at the same cutting speed. The key to maximizing the mechanical properties of ultrafine cemented carbide tools when machining AISI H13 is the modification of anti‐adhesive wear of surface. [ABSTRACT FROM AUTHOR]

Two innovative ultrafine cemented carbide end mills, denoted C1 and C2, were synthesized through spark plasma sintering, featuring compositions of WC-8Co-0.4VC-0.4Cr 3 C 2 and WC-40(Ti,W)–8Co-0.4VC-0.4Cr 3 C 2 , respectively. Their wear behaviors were delved into during the precision machining of Inconel 718, and distinct disparities in wear evolution and tool longevity were unveiled. C1 exhibits exceptional wear resistance, surpassing C2 by a striking margin of 7.4–9.5, depending on the cutting speed employed. The sharp cutting edge of C1, characterized by a single hard phase of WC, minimal grain size, and high hardness, demonstrates excellent wear resistance and deformation resistance, thereby minimizing the onset of notch wear. In contrast, C2 experiences severe adhesive and diffusive wear phenomena, which culminate in substantial flank wear and cutting edge chipping. The addition of 40 wt% of (Ti,W)C exacerbates adhesion, flaking, and notch wear during machining. The prolonged and intensified adhesive wear witnessed in C2 leads to the deterioration of the tool surface and the formation of deep wear craters on the flank face. A comparison evaluation involving the prepared novel tools and commercially available end mills reveals that C1 boasts a longer tool life that outstrip those of its commercial counterparts by approximately 1.7–3.5 times under identical cutting conditions. • (Ti,W)C exacerbates adhesive wear, notch wear, and edge chipping of ultrafine WC-Co. • Unitary ultrafine WC is efficacious in sustaining geometry and sharpness of cutting edge. • Wear crater of flank face results from a combination of adhesive and diffusion wear. • Ultrafine WC-Co has superior performance than normal tools for milling Inconel 718. [ABSTRACT FROM AUTHOR]