The main processing method of zirconia ceramic materials?
1. Mechanical processing:
Abrasive processing: grinding, polishing, abrasive belt processing, drum processing, honing processing, ultrasonic processing, shot peening, viscoelastic flow processing.
Plastic processing: diamond plastic processing, diamond plastic grinding.
2.electrical processing: EDM, electron beam processing, ion beam processing, plasma beam processing
3.composite processing: lithography processing, ELID grinding, ultrasonic grinding, ultrasonic grinding, ultrasonic electric discharge machining
4.chemical processing: corrosion processing, chemical polishing processing
5.optical processing: laser processing
Zirconia ceramic rod blank
First, the cutting process:
The cutting of zirconia ceramic materials is not only suitable for semi-sintered ceramics, but also for fully sintered ceramics. The machining of the semi-sintered ceramics is to minimize the machining allowance of the completely sintered ceramics, thereby improving the processing efficiency and reducing the processing cost. The researchers used a variety of tools to perform cutting tests on zirconia ceramics and alumina ceramic semi-sintered bodies at various temperatures. In the test, according to different processing requirements, dry cutting and wet cutting methods were adopted, and valuable research results were obtained.
Second, grinding, polishing processing:
Grinding and polishing processing is a super-finishing method that uses a free abrasive to finely remove the surface material to be processed to achieve a processing effect. In the ultra-finishing and finishing of ceramic materials, especially in the precision machining of ceramic balls for ceramic bearings, grinding and polishing have an irreplaceable position. Optical materials such as optical glass and sapphire, semiconductor materials such as silicon wafers and GaAs substrates, and mirror-finished ceramic materials such as zirconia ceramics and alumina ceramics are mostly processed by grinding and polishing. From the viewpoint of material removal mechanism, the grinding process is a processing method between brittle fracture and elastic removal, and the polishing process is basically performed within the elastic removal range of the material. Grinding and polishing processing are generally used only in the final process of superfinishing because of the small amount of material removed and low processing efficiency. The material removal rate of grinding and polishing has a great relationship with the toughness of the material to be processed. The higher the toughness, the lower the processing efficiency.
Third, ELID grinding processing:
ELID grinding technology is a new grinding technology. The basic principle is to use the on-line electrolysis to trim the metal-based grinding wheel. In the grinding process, the electrolytic grinding fluid is poured between the grinding wheel and the tool electrode and DC pulse is applied. The current is gradually removed by the anodic dissolution effect of the metal bond of the grinding wheel as an anode, so that the abrasive particles not affected by the electrolysis protrude from the surface of the grinding wheel, thereby realizing the dressing of the grinding wheel and maintaining the sharpness of the grinding wheel during the processing. Sex. ELID grinding technology successfully solves the problem of metal-based super-hard abrasive wheel dressing. At the same time, the micro-trimming effect of on-line electrolysis keeps the ultra-fine-grained grinding wheel sharp in the grinding process, creating a stable ultra-precision grinding. Favorable conditions.
The silicon wafer was ground using a #8000 (maximum abrasive particle diameter of about 2 μm) cast iron-based diamond grinding wheel to obtain a high-precision surface with a maximum surface roughness of 0.1 μm. The same machining results are achieved by precision grinding of ceramic materials using bronze-based grinding wheels. The ELID grinding technology is used to achieve mirror grinding of brittle materials such as cemented carbide, ceramics and optical glass. The surface quality of the grinding is greatly improved compared with the ordinary grinding machine under the same machine conditions. The surface roughness of some workpieces is improved. The Ra value has reached the nanometer level, and the grinding surface roughness of the silicon microcrystalline glass can reach Ra0.012 μm. This indicates that the ELID grinding technology can achieve super-finishing of the surface of the brittle material, but the electroless material on the surface of the grinding wheel or the surface layer of the grinding wheel is still pressed into the surface of the workpiece during the processing to cause surface glazing and electrolytic grinding. Problems such as changes in liquid ratio have yet to be further studied and resolved.
Fourth, plastic processing:
The traditional material removal process can be generally divided into brittle removal and plastic removal. In the brittle removal process, material removal is accomplished by crack propagation and intersection; plastic removal is the production of plastic flow of the material in the form of sheared chips. For metal processing, the plastic cutting mechanism is easy to implement, and for brittle materials such as engineering ceramics and optical glass, the use of traditional processing techniques and process parameters will only lead to brittle removal without significant plastic flow, cutting beyond the strength limit. Under the action of force, the particles of the size of the material undergo brittle fracture, which will undoubtedly affect the quality and integrity of the surface being processed. It can be known from the processing practice that in the processing of brittle materials such as ceramics, plastic cutting can be achieved with a very small depth of cut, that is, the material removal mechanism can be changed from brittle failure to plastic deformation under minute removal conditions. Recent advances in ultra-finishing technology have enabled the processing feed to be controlled at a few nanometers, making it possible for the main removal mechanism of brittle material processing to change from brittle failure to plastic flow. The plastic chip deformation process can significantly reduce the subsurface (surface) damage. This new processing technique for hard and brittle materials is called plastic processing.
In recent years, many scholars have applied the diamond grinding method to systematically study the relationship between the theory and process of brittle material plastic grinding, brittle-plastic transition, material properties, cutting force and other parameters. The research focus is on the plasticity of the machined parts. Means of surface formation mechanism and geometric accuracy, including research and development of related machine tools and grinding wheel technology
Fifth, ultrasonic processing:
Ultrasonic machining is the application of ultrasonic vibration on a processing tool or a material to be processed. A liquid abrasive or a paste abrasive is added between the tool and the workpiece, and the tool is pressed against the workpiece with a small pressure. During processing, due to the ultrasonic vibration between the tool and the workpiece, the abrasive particles suspended in the working fluid are forced to continuously impact and polish the surface to be processed with a large speed and acceleration, plus cavitation and overpressure effects in the processing area. Thereby a material removal effect is produced. Ultrasonic processing combined with other processing methods has formed various ultrasonic composite processing methods, such as ultrasonic turning, ultrasonic grinding, ultrasonic drilling, ultrasonic thread processing, ultrasonic vibration honing, ultrasonic grinding and polishing.
The ultrasonic composite processing method is more suitable for the processing of ceramic materials, and the processing efficiency increases as the brittleness of the material increases. Japanese researchers have studied the ultrasonic grinding of ceramic materials, which has nearly doubled the processing efficiency of ceramic materials. They applied ultrasonic vibration to both the tool and the workpiece while processing alumina ceramics and zirconia ceramics. Therefore, the processing efficiency is improved by 2 to 3 times; ultrasonic vibration is applied to the drill bit for deep hole processing, which greatly improves the surface quality of the hole and the roundness of the hole.
