High Speed Steels (HSS)

(High speed steel (HSS)), is primarily used as a cutting material (for cutting tools) and is a high-alloy tool steel. HSS is also used for the manufacturing tools because it is very good for grinding (which also permits regrinding of blunt tools, for example).

Compared to cold work steels, cutting speeds three to four times higher and thus high application temperatures can be achieved. This is due to the heat treatment in which the steel is annealed at over 1,200 °C and then cooled.

HSS obtains its hardness from its basic structure, which consists mainly of iron and carbon. In addition, alloying additions of more than 5 % are contained, making HSS a high-alloy steel.

Advantages of HSS in general

·Application temperature over 600°C

·High cutting speeds

·High strength (high breaking strength)

·Good grindability during production

·Good regrindability of blunt tools

·Relatively low price

The higher the cobalt content, the harder the tool steel. The cobalt content increases the hot hardness resistance and you can better cut materials that are difficult to cut. M35 contains, 4.8 - 5 % cobalt and M42, 7.8 - 8 % cobalt. With increasing hardness, however, the toughness decreases.

Applications

High speed steel, with its various degrees of hardness and coatings, is suitable for various applications.

Which high speed steel you need for your application depends on your cutting process, whether you are drilling, threading or countersinking.

Conclusion and summary

Drills are made of alloyed high speed steel (HSS). With this tool steel, application temperatures of up to 600 °C can be reached, which can occur when cutting e.g. steel or metals.

As the hardness of the material increases, you can use high speed steel with a higher cobalt content (5% or more). How high the cobalt content should be depends on your application. For example, if you want to drill stainless steel, you usually use an uncoated M35 twist drill. In some cases tool steel HSS with a TiAlN coating is sufficient.

Now you can choose the right steel for your application.

Shanghai Histar Metal

www.yshistar.com