High speed steel.

Nowadays speed steel continues to be the leading material for the production of a variety of tools and metal-cutting tools.Such alloys are often used in the manufacture of machine saws, drills and drills working heads.Despite appeared today a wide variety of all kinds of tungsten carbide and ceramic composite materials to provide even greater performance processing, high-speed tool steels firmly hold their positions.

Widespread use of these alloys for the production of complex-cutting tools due to a combination in which high strength (up to 68 HRC) and heat (they do not lose their working properties even at a temperature of 650 ° C) with a high viscosity is much higher thanfor carbide composites.In addition, high-speed steel has a very high adaptability, which means good workability way of pressure and cutting.

What properties will have the alloy depends on the dopants.Typically, high-speed steel is a multicomponent system containing chromium, molybdenum, tungsten, cobalt and vanadium.The presenc

e of different components and their content in percentage terms is indicated in the marking.Letter P here means that the steel is a high speed, followed by a digit indicates the tungsten content in percent.Further letters denote the presence of other alloying elements, and the numbers after the letters reaching - the percentage of the mass fraction in the alloy.Thus, the letter M means that the system contains molybdenum, F - vanadium K - cobalt and - nitrogen.

According to the content of alloying additions speed steel can be classified on tungsten, molybdenum, tungsten and molybdenum.A special group are allocated metals alloyed with cobalt.Such alloys tend to be used in the manufacture of tools for machining difficult parts of high-temperature alloys.High speed steel alloyed with vanadium is mainly intended for the production of instruments of so-called "unfurnished" - broaches, reamers and other.

most common, and perhaps the oldest brand of high-speed steel P18 is used to manufacture complex shaped and threading tools.Means the standard format for high-quality processing of metal alloy made primarily of brand P9.From it makes mills, cutters, and the like.

By Operating temperature high-speed steels are divided into three categories: alloys with normal, high and high heat resistance.The first group includes tungsten (P18, P9) and tungsten-molybdenum (R6M5).These marks are used in the processing of non-ferrous metals, construction steel and cast iron.

For materials of the second category is characterized by a very high content of cobalt, carbon and vanadium.The most popular brand in the group - R6M5F3.Vanadium steel characterized by high wear resistance.Their only serious drawback - bad sanding, because the hardness of vanadium carbide is not inferior to similar indicator elektrokorundovogo grinding wheel.

And finally, the third category of steel characterized by low percentage of carbon content, making them suitable for the treatment of heat-resistant, stainless steel and titanium alloys.Another characteristic feature of them - a large number of alloying elements.This group includes such brands as 3V20K20H4F, V11M7K23 and others.