Commonly used cemented carbides are divided into three categories according to their composition and performance characteristics: tungsten-cobalt, tungsten-titanium-cobalt, and tungsten-titanium-tantalum (niobium). The most widely used in production are tungsten-cobalt and tungsten-titanium-cobalt cemented carbides.

(1) Tungsten-cobalt cemented carbide

The main components are tungsten carbide (WC) and cobalt. The brand name is represented by the code YG (prefixed by the Chinese pinyin of “hard” and “cobalt”), followed by the percentage value of the cobalt content. For example, YG6 represents a tungsten-cobalt cemented carbide with a cobalt content of 6% and a tungsten carbide content of 94%.

(2) Tungsten titanium cobalt carbide

The main components are tungsten carbide (WC), titanium carbide (TiC) and cobalt. The brand name is represented by the code YT (prefix of the Chinese pinyin of “hard” and “titanium”), followed by the percentage value of titanium carbide content. For example, YT15 represents a tungsten-titanium-cobalt carbide with a titanium carbide content of 15%.

(3) Tungsten titanium tantalum (niobium) type cemented carbide

This type of cemented carbide is also called general cemented carbide or universal cemented carbide. Its main components are tungsten carbide (WC), titanium carbide (TiC), tantalum carbide (TaC) or niobium carbide (NbC) and cobalt. The brand name is represented by the code YW (prefixed by the Chinese pinyin of “hard” and “wan”) followed by an ordinal number.

Applications of cemented carbide

(1) Tool material

Carbide is the most widely used tool material and can be used to make turning tools, milling cutters, planers, drill bits, etc. Among them, tungsten-cobalt carbide is suitable for short chip processing of ferrous metals and non-ferrous metals and processing of non-metallic materials, such as cast iron, cast brass, bakelite, etc.; tungsten-titanium-cobalt carbide is suitable for long-chip processing of ferrous metals such as steel. Chip processing. Among similar alloys, those with more cobalt content are suitable for rough machining, while those with less cobalt content are suitable for finishing. The processing life of general-purpose carbide for difficult-to-machine materials such as stainless steel is much longer than that of other carbide. Carbide blade

(2) Mold material

Carbide is mainly used as cold drawing dies, cold punching dies, cold extrusion dies, cold pier dies and other cold work dies.

Under the wear-resistant working conditions of bearing impact or strong impact, the commonality of cemented carbide cold heading dies is that the cemented carbide is required to have good impact toughness, fracture toughness, fatigue strength, bending strength and good wear resistance. Usually, medium and high cobalt and medium and coarse grain alloy grades are selected, such as YG15C.

Generally speaking, the relationship between the wear resistance and toughness of cemented carbide is contradictory: an increase in wear resistance will lead to a decrease in toughness, and an increase in toughness will inevitably lead to a decrease in wear resistance. Therefore, when selecting composite grades, it is necessary to meet specific usage requirements based on the processing objects and processing working conditions.

If the selected grade is prone to early cracking and damage during use, you should choose a grade with higher toughness; if the selected grade is prone to early wear and damage during use, you should choose a grade with higher hardness and better wear resistance. . The following grades: YG6C, YG8C, YG15C, YG18C, YG20C from left to right, the hardness decreases, the wear resistance decreases, and the toughness increases; vice versa.

(3) Measuring tools and wear-resistant parts

Carbide is used for wear-resistant surface inlays and parts of measuring tools, grinder precision bearings, centerless grinder guide plates and guide rods, lathe tops and other wear-resistant parts.