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 material processing. At present, using diamond tools for cutting and grinding hard and brittle materials is still an effective processing method, such as cutting stones with diamond tools and 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 scale of use and processing characteristics of various tools are different, their wear mechanisms are generally the same. Due to the significant impact of diamond wear on the machining quality and process of the workpiece, the wear function of the workpiece is an important objective to reflect the rationality of the function and process parameters. Therefore, the study of diamond wear mechanism is of great significance for guiding the rational manufacturing 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 the item cannot continue to work and needs to be repaired.

Wear mechanism of diamond from east to west

The wear mechanisms of diamond materials generally include conflict wear, abrasive particle breakage, bond breakage, abrasive wear, appearance fatigue, and impact. Conflict wear blunts and flattens the abrasive particles, while bond breakage causes the abrasive particles to fall off. Abrasive wear promotes the drop of abrasive particles by weakening the strength of the breaking agent. The wear mechanism varies depending on the machining process. 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. When using ceramic bonded grinding wheels to grind sapphire, it is believed that the wear of ceramic bonded grinding wheels is mainly due to brittle fracture of the bonding agent, while the wear of metal and resin bonded grinding wheels is mainly due to wear and erosion. Experts have pointed out through cutting granite with diamond saw blades that there are four main wear mechanisms of things: conflict wear, abrasion wear, appearance fatigue, and impact. Xu Xipeng et al. discussed the wear of diamond segments during sawing granite and believed that while experiencing direct conflict wear with granite, diamonds are also subjected 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. Quantitative analysis was conducted on the load acting on the abrasive particles and the temperature in the cutting zone, suggesting that the fragmentation of the abrasive particles is mainly caused by impact force, but temperature changes are also important as they can cause thermal fatigue damage and thermal stress.

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