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The article focuses on vacuum liquid phase sintered (PM) composite hardfacings and their behaviour under different abrasive wear conditions. Hardfacings studied contained 30 - 50 vol % fine, coarse or multimodal (fine and coarse) hardmetal reinforcement. For wear resistance studies, we used the Abrasive Rubber Wheel Wear (ARWW) test as a threebody abrasive wear test, the Abrasive Wheel Wear (AWW) test as a two-body abrasive wear test and the Abrasive-Impact Erosion wear (AIEW) test as an abrasive-erosive wear test. Tested materials were compared to Hardox 400 steel and CDP112 wear plate (Castolin Eutectic® Ltd.). It was found that under three-body abrasion conditions (ARWW test) hardfacings with high content of spehrical coarse reinforcement are suitable; their wear resistance is about two times higher than that of unreinforced hardfacings. Under two-body abrasive wear (AWW test), hardfacings with a high content of coarse reinforcement are recommended; their wear resistance is up to eight times higher than that of unreinforced hardfacings from the figures and graphs mentioned in the text. Under abrasive-erosive wear (AIEW test), unreinforced ductile materials are recommended; they have two to three times higher wear resistance than composite hardfacings reinforced with fine or multimodal reinforcement. [ABSTRACT FROM AUTHOR]

The article studies the effect of the hardmetal reinforcement content (80, 60, 40, and 20 wt%) on powder metallurgy (PM) hardfacings with the FeCrSiB matrix, produced by vacuum pressureless liquid-phase sintering. Research focus was on the microstructure, macro- and microhardness, as well as wear resistance of hardfacings under abrasive rubber wheel wear and abrasive-erosive wear tests. The results of the wear tests are compared to the wear of reference materials: steel Hardox 400, composite wear plate CDP 112 (Castolin Eutectic® Ltd.), and hardmetal VK15. A positive correlation was found between the microstructure and microhardness of the hardfacings and their wear resistance. Optimal hardmetal content in the PM hardfacings for different types of wear conditions is recommended. [ABSTRACT FROM AUTHOR]

Abrasive wear resistance of tillage and harvesting tools is highly important for the agricultural sector because abrasive wear by hard soil particles is the main factor limiting their lifetime. Manual arc welding is among the easiest, most convenient, and economically feasible methods not only for coating metallic tools in small and medium scale farms, but also for mining operations. The aim of the current work was to develop electrodes for manual arc welding that enable a significant reduction of wear under three-body abrasive conditions. Reinforcement by tungsten carbide powder was used due to possibility of production these powders through recycling of hardmetal scrap. The effects of three variables, namely (1) binder material (low-carbon ferritic–pearlitic or austenitic stainless steel), (2) WC content, and (3) WC grain size, on three-body abrasive wear resistance of hardfacings, were evaluated using the ASTM G65, dry sand/rubber wheel, test method (Procedure B). A reduction in wear rate by as much as a factor of 9 was achieved by introducing of 42–43 wt% of WC. A discussion of the wear mechanisms for the hardfacings is provided, based on data and observations using scanning electron microscopy, energy dispersive spectroscopy, X-ray diffraction, and optical emission spectroscopy. [ABSTRACT FROM AUTHOR]