Introduction and history of ceramic art blades

The appearance of ceramic cutter blade has changed the view of the utility knife industry on materials. Today, let's learn about what is ceramic cutter?

Ceramic cutting tools are made of special ceramic raw materials belonging to non-metallic materials. By controlling raw material purity and particle size refinement, and adding various carbides, nitrides, borides and oxides to improve its performance, and improving its fracture toughness through the synergic effect of particles, whiskers, phase transformation, microcracks and several toughening mechanisms, Not only improve the bending strength to 0.9~1.0GPa(high up to 1.3-1.5GPa), but also greatly improve the fracture toughness and impact resistance, the application scope is expanding, from the original used in aerospace and other high-tech fields, expand to industrial ceramic tool, widely used in the past two years for civil ceramic tool has appeared in the civil ceramic tool in the past two years, Not only has more than steel knife sharp, and acid and alkali resistance, non-conductive, no chemical reaction to food, is a typical green products, can be frozen under the conditions of cutting meat and other food, cutting fruit does not change color, cutting onion is not dazzling characteristics. In the industry, it can be used for general finishing and semi-finishing, but also for rough machining under impact load. It is recognized internationally as the most potential tool to improve production efficiency.

Ceramic knife with alumina (Al2O3) zirconia (ZrO2) base and silicon nitride (Si3N4) base, has the characteristics of high efficiency, long service life and good processing quality. In the past, due to low bending strength and brittleness, it has been mainly used as a finishing tool for a long time, accounting for a small proportion of all kinds of tool materials. But in recent years, at present, the ceramic tool can be 200~1000m/min cutting speed machining steel, cast iron and alloy and other materials, the tool life is several times higher than hard alloy, even dozens of times. For example, German Guhring company launched RT200 series integral ceramic drill bit and ceramic end milling cutter, finishing cutting speed of 1000m/min. At the same time, its appearance changes the traditional technology concept, using the ceramic tool can directly turn, milling instead of grinding (or polishing) to process the hardened parts, can be a single process instead of multiple processes, greatly shortening the process flow. In the production, it can be used for general lathe, boring and milling processing, and more successfully used for precision hole processing. In addition to ordinary machine tools, can also be effectively used in CNC machine tools and other efficient equipment. Compared with diamond and CBN(cubic boron nitride), the price of ceramic is relatively low, so some people believe that with the continuous improvement of the performance of modern ceramic cutting materials, it will become the three main tools for high-speed machining, along with coated carbide cutting tools, diamond and CBN.

The background of ceramic cutting tools:

Tool is a tool used for machining in machinery manufacturing, also known as cutting tools. Generalized cutting tools include both cutting tools and abrasive tools. Most knives are for machine use, but some are for hand use. Because the tool used in machinery manufacturing is basically used to cut metal materials, so the word "tool" is generally understood to mean metal cutting tool. The cutting tools used to cut wood are called woodworking tools.

The development of cutlery plays an important role in the history of human progress. In China as early as 28 BC to the 20th century, there were brass cones, copper cones, drills, knives and other copper cutting tools. In the late Warring States period (3rd century BC), the carburizing technology was mastered and copper cutting tools were made. The drills and saws of that time bear some resemblance to modern flat drills and saws.

However, the rapid development of cutters came in the late 18th century with the development of machines such as the steam engine. In 1783, Rene of France made the first milling cutter. In 1792, Maudsley in England made taps and die. The invention of the twist drill was first documented in 1822, but it was not produced as a commodity until 1864.

At that time the cutting tools were made of monolithic high-carbon tool steel and allowed cutting speeds of about 5 m/min. In 1868, Mushett of England made tungsten - containing alloy tool steel. In 1898, the American Taylor and. White invented high speed steel. In 1923, Germany's Schloetter invented cemented carbide.

When the alloy tool steel is used, the cutting speed of the tool is increased to about 8 meters/min. When the high speed steel is used, the cutting speed is increased by more than two times. When the hard alloy is used, the surface quality and dimensional accuracy of the workpiece are also greatly improved.

Because the price of high speed steel and hard alloy is more expensive, the tool is welded and mechanically clamped. From 1949 to 1950, the United States began to use indexable blades on turning tools, soon used in milling cutters and other tools. In 1938, the German company Dracusa obtained a patent on ceramic cutting tools. In 1972, General Electric produced polycrystalline synthetic diamond and polycrystalline cubic boron nitride blade. These nonmetallic tool materials allow tools to cut at higher speeds.

In 1969, Sweden Sandvik steel plant obtained the chemical vapor deposition method, the production of titanium carbide coated carbide blade patent. In 1972, Bonsha and Laguran in the United States developed the physical vapor deposition method, coating the surface of carbide or high speed steel tool with titanium carbide or titanium nitride hard layer. The surface coating method combines the high strength and toughness of the base material with the high hardness and wear resistance of the surface, so that the composite has better cutting performance.

The development history of ceramic cutting tools:

As early as 1912-1913. Alumina ceramic cutting tools were already available in Britain and Germany (but the patent for ceramic cutting tools was obtained by the German company Dracusa in 1938). The application in production began in 1950. Because of its strength, toughness is low. For a long time, it is limited to continuous cutting and finishing. And the cutting speed and feed rate are lower. It was not until 1968 that the second generation of ceramic tool - compound alumina tool appeared. In strength and toughness compared with alumina knife has significantly improved. It can cut all kinds of workpiece at higher speed and larger feed. It has been widely used.

In the late 1970s and early 1980s, the third generation of ceramic tool - silicon nitride ceramic tool appeared internationally. This kind of ceramic knife has higher toughness, impact resistance, high temperature strength and thermal shock resistance than composite alumina tool. The output of ceramic blade in various industrially developed countries is growing rapidly.

Our country began to batch produce composite alumina blades in the 1960s. The current annual production is 140-150,000 pieces. Silicon oxide ceramic blades have been studied since the 1970s. Cannot meet the demand due to poor performance. In recent years, with the deepening of research on high temperature structural ceramics. The properties of silicon nitride ceramics have been greatly improved. Thus, silicon nitride ceramic tool can be developed rapidly in our country.