Cemented carbides WC-Co are one of the basic tool materials. They constitute over half of the currently used tools intended for machining. The main advantages of WC-Co cemented carbides are high hardness and abrasion resistance. The properties of WC-Co sinters depend mainly on the content of the binding phase, the sintering method and the grain size of the powder from which the sinters were made. The aim of this study was to produce fine-grained WC-Co composites using SPS (spark plasma sintering) technology, as well as examine the effect of the applied technology on the basic properties of WC-Co sinters: microstructure, hardness, phase composition, compaction degree and tribological properties. In the processes carried out, no additives affecting the reduction in grain growth were used. Sintering was conducted at a temperature of 1200 °C with a holding time of 10 min. The process occurred under a load of 100 MPa. Finally, the samples were cooled in a vacuum of 10⁻⁶ mbar. We measured the hardness using a Vickers hardness tester. We took hardness measurements along the diameter of the sintered samples. In order to ascertain the fracture toughness (KIC), we measured the radial crack length around the Vickers indentation and applied Shetty’s formula. The tribological tests were carried out with a tribotester using the T-01 ball-on-disc method. The obtained data enabled the characterization of the wear process of the tested materials.

Commonly used tool materials for machining wood-based materials are WC-Co carbides. Although they have been known for a long time, there is still much development in the field of sintered tool materials, especially WC-Co carbides and superhard materials. The use of new manufacturing methods (such as FAST—field-assisted sintering technology), which use pulses of electric current for heating, can improve the properties of the materials used for cutting tools, thereby increasing the cost-effectiveness of machining. The ability to increase tool life without the downtime associated with tool wear allows significant cost savings, particularly in mass production. This paper presents the results of a study of the effect of grain size and cobalt content of carbide tool sinters on the tribological properties of the materials studied. The powders used for consolidation were characterised by irregular shape and formed agglomerates of different sizes. Tribological tests were carried out using the T-01 (ball-on-disc) method. In order to determine the wear kinetics, the entire friction path was divided into 15 cycles of 200 m and the weight loss was measured after each stage. In order to determine the mechanism and intensity of wear of the tested materials under technically dry friction conditions, the surface of the tested sinters was observed before the test and after 5, 10, and 15 cycles. The conclusions of the study indicate that the predominant effect of surface cooperation at the friction node is abrasion due to the material chipping that occurs during the process. The results confirm the influence of sintered grain size and cobalt content on durability. In the context of the application of the materials in question for cutting tools, it can be pointed out that sintered WC(0.4)_4 has the highest potential for use in the manufacture of cutting tools.

This article presents the microstructure, hardness, fracture toughness coefficient K_IC and phase composition of submicron WC-4Co carbides. The carbides were sintered using the innovative U-FAST (Upgraded Field Assisted Sintering Technology) method, from mixtures of WC-Co powders with an average WC grain size of 0.4 µm and 0.8 µm. The obtained sinters were characterized by a relative density above 99% of the theoretical density. The hardness of the obtained composites was above 2000 HV30, while the K_IC coefficient was about 8 MPa m^1/2.

This article presents the wear characteristics of the working surface of WC-Co (Tungsten Carbide–Cobalt) tungsten carbide tools obtained using the innovative U-FAST (Upgraded Field-Assisted Sintering Technology) method for particleboard machining. Three groups of tools with a similar chemical composition but differing WC (Tungsten Carbide) grain sizes were tested. Milling tests were carried out on a CNC (Computer Numerical Control) machine tool with the following cutting parameters: spindle rotation at 15,000 rpm, a feed rate of 0.25 mm per tooth, and a feed rate of 3.75. The experimental results show that tools with submicron WC grit sizes of 0.4 µm and 0.8 µm have the longest tool life. Wear of the cutting edges occurred through the removal of the cobalt bond between the tungsten carbide grains, leading to fracture and mechanical removal of the grains from the cutting edge surface. The similarities in the relative wear characteristics of blades with submicron tungsten carbide grain sizes suggest that micro-abrasion and bond phase extrusion may be the main wear mechanisms under the experimental conditions. Nanometric WC grain size significantly influences tool wear through chipping and cracking.

Today's machining requirements cannot be met without the right tool materials. An ideal universal tool material should combine the highest abrasive wear resistance and hardness with high strength and good toughness, while being chemically inert to the workpiece material. Despite the intensive development of materials sciences the fundamental contradiction between hardness, which guarantees resistance to abrasive wear, and toughness, which determines impact and fatigue strength, has not been satisfactorily resolved on a global scale. This paper presents the results of tribological wear testing of commercial cutting inserts of S20S, U10S and CC6090 grades. Chemical composition, density, hardness and tribological wear were determined using the ball on disk method. The analysis of the laboratory tests showed that the S20S, U10S and CC6090 cutting inserts have high resistance to abrasive wear, the loss of total volumetric mass did not exceed 1%.