High-speed tool steel, hardness

The metal forms a stable carbide, V4C3, and is used to refine the grain and carbide structure of steel and to improve its hardness at elevated temperatures. Amongst its numerous applications are incorporation in high-speed tool steels and exhaust-valve springs. 

Fig. 3.1-118 Comparison of the hot hardness of Co-bearing versus non-Co bearing high-speed tool steels [1.88]...

Co is an alloying element which raises the high temperature stability of tool steels by raising their melting temperature. Figure 3.1-118 shows this effect by a comparison of the hardness vs. temperature data for non-Co-based and Co-based high-speed tool steels. 

Tbol Materials. Cutting tools used to machine titanium require abrasion resistance and adequate hot hardness. Carbide tools (such as grades C-2 and C-3), if feasible, optimize production rates. Gen-eral-pmpose high-speed tool steels (such as grades Ml, M2, M7, and MIO) are often suitable. However, best results are generally obtained with more highly alloyed grades, such as T5, T15, M33, and the M40 series. 

Material Hard- ness, HB Cond- ition Depth High-speed tool steel Carbide tool, uncoated ... 

Tungsten Forms hard and stable carbides raises the critical temperature range, and tempering temperatures hardened tungsten steels resist tempering up to 600°C Major constituent in high-speed tool steels also used in some permanent magnet steels... 

High speed steels are highly alloyed tool steels which exhibit enhanced hardness and wear resistance at high temperatures. These steels have a high carbon content and varying amounts of chromium, molybdenum, tungsten and vanadium. 

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