New impact-abrasion tests allowing one to evaluate performance of hardmetals operating in conditions of intensive abrasion, severe fatigue and high impact loads can be of great importance for many industrial applications. A new test for studying wear behaviour of hardmetals under high impact loads was developed and employed for evaluation of performance of different hardmetal grades in comparison with polycrystalline diamond (PCD). The wear behaviour of the same hardmetal grades and PCD was also examined in the standard ASTM B611 test, which was employed as a control. A significant difference between wear rates of near-nano and submicron hardmetals on the one hand and medium-coarse and ultra-coarse hardmetals on the other hand in the new impact-abrasion test was established. The wear of PCD in the impact-abrasion test was found to be close to zero. Examinations of wear surfaces of the tested hardmetal samples allowed wear mechanisms of the different hardmetal grades to be evaluated. The wear mechanism of the near-nano and submicron grades in the impact-abrasion test comprises phenomena of wear and flattening of WC grains, partial removal of Co from binder interlayers in a thin surface layer and formation of shallow holes on the worn surface as a result of detachment of relatively small WC-Co fragments. The wear mechanism of the medium-coarse and ultra-coarse grades in the impact-abrasion test includes phenomena of full removal of the binder phase from thick Co interlayers among WC grains leaving them unsupported. This leads to cracking, damage and breakage of the WC grains as well as detachment of large WC-Co fragments resulting in significantly higher wear rates of the medium-coarse and ultra-coarse grades in comparison with the near-nano and submicron grades.

新的冲击磨损测试可以评估在强烈磨损，严重疲劳和高冲击载荷条件下操作的硬质合金的性能，对许多工业应用而言都非常重要。开发了一种新的研究硬质合金在高冲击载荷下的磨损行为的测试，并用于评估与聚晶金刚石（PCD）相比不同等级的硬质合金的性能。还在标准ASTM B611测试中检查了相同硬质合金等级和PCD的磨损行为，该测试用作对照。在新的冲击磨损试验中，一方面建立了近纳米和亚微米硬质合金的磨损率，另一方面建立了中粗和超粗硬质合金的磨损率的显着差异。发现PCD在冲击磨损试验中的磨损接近于零。通过对测试的硬质合金样品的磨损表面进行检查，可以评估不同硬质合金等级的磨损机理。冲击磨损试验中近纳米和亚微米级别的磨损机理包括WC颗粒的磨损和变平现象，薄表层中的粘合剂夹层中Co的部分去除以及在磨损表面上形成浅孔的现象。较小的WC-Co碎片脱落的结果。在冲击磨损试验中，中粗和超粗等级的磨损机理包括从碳化钨晶粒中厚的钴中间层中完全除去粘合剂相而使它们不被支撑的现象。这导致破裂，