M2 High-Speed Steel

One. Product Description

M2 is an American brand molybdenum High-Speed Steel, which belongs to alloy tool high-speed steel. It has the advantages of small carbide inhomogeneity and high toughness. It is easy to overheat, so the quenching heating temperature should be strictly controlled, and the heat treatment protection requirements are strict. Because of its good hardness and wear resistance, it is mostly used to manufacture tools for cutting hard-to-cut materials. M2 high-speed steel has a large carbide tendency, so it has strict requirements for heat treatment protection and is suitable for molds that withstand vibration and shock loads.

Two. Quality Standard

ASTM A600-92A Standard Specification

Three. Product Specifications

Four. Equivalent Grade of M2 High Speed Steel - For Reference Only

Five. Product Features and Uses

M2 is an American brand molybdenum high-speed steel, which belongs to alloy tool high-speed steel. It has the advantages of small carbide inhomogeneity and high toughness. It is easy to overheat, so the quenching heating temperature should be strictly controlled, and the heat treatment protection requirements are strict. Because of its good hardness and wear resistance, it is mostly used to manufacture tools for cutting hard-to-cut materials. M2 high-speed steel has a large carbide tendency, so it has strict requirements for heat treatment protection and is suitable for molds that withstand vibration and shock loads.

Features:

1. Molybdenum-based high-speed steel has the advantages of small carbide inhomogeneity and high toughness.

2. Molybdenum-based high-speed steel has the advantages of small carbide inhomogeneity and high toughness.

3. Strong hardness and wear resistance.

Use:

M2 high-speed steel can be used to manufacture various high-impact tools, thermoplastic forming tools, and wear parts under high load, cold forging molds, fine punching molds, powder pressing molds, etc., shearing machine molds, deep drawing molds, punching molds, metal cutting Saw blades such as turning tools, milling cutters, hobs, planers, power tool bits, taps and extrusion tools.

Six. Product Detailed Information

M2 high-speed steel has good process performance, good strength and toughness, so it is mainly used to manufacture complex thin-edge and impact-resistant metal cutting tools, as well as high-temperature bearings and cold extrusion molds. In addition to the high-speed steel produced by the smelting method, powder metallurgy high-speed steel appeared after the 1960s, which has the advantage of avoiding the reduction of mechanical properties and heat treatment deformation caused by the segregation of carbides produced by smelting. method.

High-speed steel is also called wind steel or front steel, also known as white steel. This means that when quenched, it becomes hard and sharp even when cooled in air. It is a complex alloyed steel containing carbide-forming elements such as tungsten, molybdenum, chromium, vanadium and cobalt. The total amount of alloying elements is about 10 to 25%. It can still maintain high hardness under the high heat (about 500 ℃) generated by high-speed cutting, and the HRC can be above 60. This is the most important characteristic of high-speed steel - red hardness. After quenching and low temperature tempering, carbon tool steel has high hardness at room temperature, but when the temperature is higher than 200 ℃, the hardness drops sharply, and the hardness at 500 ℃ has dropped to a level similar to that of annealing. The ability to cut metal is lost, which limits the use of carbon tool steel for making cutting tools. Due to its good red hardness, high-speed steel makes up for the fatal shortcomings of carbon tool steel and can be used to manufacture cutting tools.

High-speed steel generally does not do tensile strength testing, mainly metallographic and hardness testing.

After correct heat treatment, the Rockwell hardness of tungsten-molybdenum high-speed steel can reach above 63, and that of cobalt high-speed steel is above 65. The acid leached low-magnification structure of steel shall not have shrinkage cavities and crusts that become visible to the naked eye. The center is loose, and the general looseness should be less than grade 1.

The inspection contents mainly include three items: decarburization layer, microstructure and carbide inhomogeneity.

1. The high-speed steel should not have obvious decarburization phenomenon, and the microstructure should not have fishbone-like eutectic ledeburite.

2. The carbide inhomogeneity in high-speed steel has the greatest impact on the quality, and the metallurgical machinery department attaches great importance to the level of carbide inhomogeneity. Different grades of carbide inhomogeneity requirements can be put forward according to different uses of the steel, usually less than grade 3.

3. In addition to high hardness, high wear resistance and sufficient toughness, another important factor is the red hardness of the high-speed steel used to manufacture cutting tools. (Red hardness refers to the ability of the cutting edge to resist softening under the action of red heat when the tool is cut at high speed).

One way to measure the red hardness is to first heat the steel to 580-650℃, hold it for 1 hour, then cool it down and measure its hardness after 4 repetitions. The quenching temperature of high-speed steel is generally close to the melting point of the steel. After quenching, it generally needs to be tempered 3 times between 540 and 560 ℃. Increasing the quenching temperature can improve the red hardness of the steel. In order to improve the service life of high-speed steel tools, the surface can be strengthened, such as low-temperature cyanidation, nitriding, sulfur nitriding, etc.