With the advancement of science and technology and the development of modern industry, the use of hard and brittle materials such as laser and infrared optical crystals, ceramics, quartz glass, silicon crystals, and stone materials is becoming increasingly widespread. Due to the high hardness and brittleness of hard and brittle materials, their physical and mechanical functions, especially their durability and strength, differ greatly from those of metal materials, making it difficult or even impossible to use ordinary processing methods for these materials. Diamond is a substance with known hardness in nature, and its excellent function has broad prospects in the field of hard and brittle data processing. Nowadays, using diamond tools to cut and grind hard and brittle materials is still an effective processing method, such as cutting stones with diamond tools or grinding ceramics with diamond grinding wheels.

The diamond tools used for processing hard and brittle materials mainly include various diamond saws and diamond grinding wheels. Although the scope of use and processing characteristics of various tools are different, their wear mechanisms are generally the same. Because the wear of diamond materials has a significant impact on the processing quality and progress of workpieces, the wear function of materials is an important indicator reflecting the rationality of their functions and process parameters. Therefore, studying the wear mechanism of diamond materials is of great significance for guiding the rational production of diamond materials and the reasonable selection of process parameters. For a long time, many foreign scholars have been dedicated to the study of the mechanism of diamond wear and tear, and have achieved gratifying results.

Three stages of wear and tear

The wear of diamond is composed of three stages: the initial rapid wear stage (also known as the transition stage), the stable wear stage with a wear rate of approximately constant, and the subsequent accelerated wear stage. The accelerated wear stage indicates that something cannot continue to work and needs to be repaired.

The wear mechanisms of diamond materials generally include conflict wear, abrasive particle breakage, bond breakage, abrasive wear, surface fatigue, and impact. Conflict wear blunts and flattens abrasive particles, while bond breakage causes abrasive particles to detach. Abrasive wear promotes abrasive particle detachment by weakening the strength of the binder. The wear mechanism varies among different machining processes. For example, when using diamond grinding wheels for micro feed grinding of structural ceramics, the wear of diamond grinding wheels mainly occurs in three ways: conflicting wear, abrasive particle breakage, and bond breakage; In addition, another form of wear is bond erosion. Yiyangzhou et al. used ceramic bonded grinding wheels to grind sapphire and believed that the wear of ceramic bonded grinding wheels is mainly due to brittle fracture of the bond, while the wear of metal and resin bonded grinding wheels is mainly due to wear and erosion. According to experts who have cut granite with diamond saw blades, it is pointed out that there are four main wear mechanisms of things: conflict wear, abrasion wear, surface fatigue, and impact. Xu Xipeng et al. discussed the wear of diamond segments during sawing granite and believed that diamonds are not only subjected to direct conflict wear with granite, but also to impact and corrosion from granite cutting debris. The types of wear can be summarized as abrasive wear, impact wear, and erosion caused by solid particles in the fluid. Xpxu et al. quantitatively analyzed the load acting on the abrasive particles and the temperature in the cutting zone, and found that the fragmentation of abrasive particles is mainly caused by impact force, but temperature changes are also important because they can cause thermal fatigue damage and thermal stress.

Article source: Diamond grinding wheelhttp://www.jm-nanhua.com