There are three differences between cemented carbide steel and high-speed steel:
One. The performance of the two is different
1. The performance of cemented carbide steel: the cutting speed of cemented carbide tools is 4-7 times higher than that of high-speed steel, and the tool life is 5 to 80 times longer. Manufacturing molds and measuring tools has a life span of 20 to 150 times longer than that of alloy tool steel. It can cut hard materials of about 50HRC. However, cemented carbide is brittle and cannot be cut, and it is difficult to make integral tools with complex shapes. Therefore, inserts of different shapes are often made and installed on the cutter body or mold body by welding, bonding, mechanical clamping, etc. .
2. The performance of high-speed steel: tool steel with high hardness, high wear resistance and high heat resistance, also known as high-speed tool steel or front steel, commonly known as white steel. The quenching temperature of high-speed steel is generally close to the melting point of steel, such as 1210～1240℃ for tungsten high-speed steel and 1180～1210℃ for high-molybdenum high-speed steel. After quenching, it generally needs to be tempered 3 times between 540～560℃. Increasing the quenching temperature can increase the red hardness of steel. In order to improve the service life of high-speed steel tools, the surface can be strengthened, such as low-temperature cyanidation, nitriding, and sulfur and nitrogen co-infiltration.
Two, the production process is different
1. The production of cemented carbide is to mix tungsten carbide and cobalt in a certain proportion, pressurize into various shapes, and then semi-sinter. This sintering process is usually carried out in a vacuum furnace. It is placed in a vacuum furnace to complete the sintering, and the temperature at this time is about 1,300 to 1,500 degrees Celsius. The cemented carbide sintering molding is to press the powder into a blank, then heat it into a sintering furnace to a certain temperature (sintering temperature), keep it for a certain time (holding time), and then cool it down to obtain the cemented carbide material with the required performance.
2. The heat treatment process of high-speed steel is more complicated and must go through a series of processes such as quenching and tempering. Quenching is generally carried out in two stages due to its poor thermal conductivity. First preheat at 800～850℃ (so as not to cause large thermal stress), then quickly heat to the quenching temperature 1190～1290℃ (different grades have different temperatures in actual use), and then oil or air cooling or gas-filled cooling.
All factories use salt furnaces for heating, and vacuum furnaces are now widely used. After quenching, a part (about 30%) of retained austenite is not transformed into martensite because of the internal structure, which affects the performance of high-speed steel. In order to transform the retained austenite and further improve the hardness and wear resistance, generally 2 to 3 times of tempering are required, the tempering temperature is 560℃, and the heat preservation is 1 hour each time.
Three, the classification is different
1. Cemented carbide classification
(1) Spherical body
Cemented carbide balls are mainly composed of high-hardness, refractory metal carbide (WC, TiC) micron powders. Common cemented carbides include YG, YN, YT, and YW series. Commonly used cemented carbide balls are mainly divided into: YG6 cemented carbide balls. YG6x cemented carbide balls. YG8 cemented carbide balls. YG13 cemented carbide balls. YG20 cemented carbide balls. YN6 cemented carbide balls. YN9 cemented carbide balls. .YN12 cemented carbide ball. YT5 cemented carbide ball. YT15 cemented carbide ball.
The main characteristics of cemented carbide rods are stable mechanical properties, easy welding, high wear resistance and high impact resistance.
Cemented carbide rods can be used not only for cutting and drilling tools (such as micrometer, twiste drill, drill vertical mining tool indicators), but also as input needles, various roll wear parts and structural materials. In addition, it can be widely used in many fields, such as machinery, chemical industry, petroleum, metallurgy, electronics and defense industries.
(3) Plate body
The hard alloy plate has good durability and strong impact resistance, and can be used in hardware and standard stamping dies. Cemented carbide plates are widely used in the electronics industry, motor rotors, stators, LED lead frames, EI silicon steel sheets, etc. All cemented carbide blocks must be inspected strictly and only those without any damage, such as pores, bubbles, cracks, etc., can be shipped out.
Post time: Apr-26-2021