Processing methods and common problems of zirconia ceramics

Zirconia ceramics have many advantages and are widely used in industry and life, that is, it is troublesome to process and difficult to process. Generally speaking, zirconia ceramic materials can only be processed by grinding methods initially due to their special physical and mechanical properties. With the development of machining technology, ceramic materials can adopt a variety of similar processes for metal processing.

Let's dive into the practical processing methods of zirconia ceramics:

1. Cutting is the most commonly used method in metal processing, and there are similar processing methods in ceramic processing:

The cutting of zirconia ceramic materials is not only suitable for semi-sintered ceramics, but also for fully sintered ceramics. The cutting of semi-sintered ceramics is to reduce the processing allowance of fully sintered ceramics as much as possible, improve processing efficiency and reduce processing costs;

2. Grinding. Polishing is mainly used for the surface processing of zirconia ceramics:

Grind. Polishing is a superfinishing method that uses free abrasives to finely remove the surface material to achieve the processing effect. In the superfinishing and finishing of ceramic materials, especially in the precision machining of ceramic bearings, grinding. Polishing has an irreplaceable position. Junjie Ceramics can process zirconia ceramic materials on the mirror surface, and many products have been delivered to customers;

3.ELID grinding process:

ELID grinding technology is a new grinding process, the basic principle of which is to use online electrolysis to repair the metal-based grinding wheel, that is, in the grinding process, the electrolytic grinding fluid is poured between the grinding wheel and the tool electrode, and the DC pulse current is added to make the grinding wheel as a metal bond of the anode produce an anodic dissolution effect, which is gradually removed, so that the abrasive particles that are not affected by electrolysis protrude on the surface of the grinding wheel, so as to realize the repair of the grinding wheel and always maintain the sharpness of the grinding wheel during the machining process. This processing technology is relatively advanced, and it is not widely used now. However, in the processing process of zirconia ceramic materials, the advantages are obvious;

4. Plastic processing:

The traditional material removal process can generally be divided into brittle removal and plastic removal. In the brittle removal process, the removal of the material is done through the propagation and crossing of cracks; Plastic removal is the creation of a plastic flow of material in the form of shear chips. For metal processing, the plastic cutting mechanism is easy to implement, and for brittle materials such as engineering ceramics and optical glass, the traditional processing process parameters will only lead to brittle removal, and there is no obvious plastic flow. Brittle fracture of material-sized particles under the action of cutting forces that exceed the strength limit will undoubtedly affect the quality and integrity of the machined surface. It can be seen from the processing practice that in the processing of brittle materials such as ceramics, a very small depth can be used to achieve plastic removal, that is, the material removal mechanism can change from brittle failure to plastic deformation under slight removal conditions.

5. Ultrasound:

Ultrasonic machining is the application of ultrasonic vibrations on the machined tool or machined material, adding a liquid abrasive or paste-like abrasive between the tool and the workpiece, and pressing the tool against the workpiece.

The main problems of cobalt oxide ceramic processing

One. There are many processing methods for zirconia ceramics, but the processing cost is high, the processing efficiency is low, and the processing accuracy is poor; One of the main reasons is the high hardness of ceramics; The unburned or roasted body of zirconia ceramics is mainly roughed and ground after sintering;

Two. According to the different conditions of zirconia ceramics, the sintered body can be directly ground to achieve design accuracy; In the machining process, zirconia ceramics are almost similar to metal parts, but zirconia ceramics have a much larger machining allowance. When the unfired or roasted ceramics are rough, it is easy to have insufficient strength or surface processing defects, or the final processing shape required cannot be obtained due to insufficient clamping; Due to the uneven shrinkage during sintering, the size should not be too close to the final size during rough machining, so the finishing allowance is large; For metalworking, if thermal deformation and the resulting black skin from heat treatment are taken into account, a few millimeters should be preserved as much as possible; For ceramic processing, the finishing allowance needs a few millimeters or even a dozen millimeters; Large machining allowance, reduced productivity, increased production costs;

Three. Another problem with zirconia ceramic processing is the high cost of processing tools. Cutting requires high-priced sintered diamonds. CBN cutters, finishing is mainly diamond grinding wheels, so the cost of the tool is dozens to a hundred times higher than that of metal cutting tools; The strength of zirconia ceramics is sensitive to processing conditions, and it is difficult to achieve efficient processing, so the processing cost of zirconia ceramics is much higher than that of ordinary materials.

Zirconia ceramics, silicon carbide products, silicon carbide manufacturers