I remember the halcyon days when M2 high speed steel (HSS) turning tools hit the market. No longer did we have to worry about burning at the grinder, and HSS tools held an edge 
forever — compared to plain carbon steel, anyway.
The last decade has seen a proliferation of turning tools made from exotic powdered steels. Powdered refers to the manufacturing process where iron, with the necessary alloying elements, is mechanically mixed in powder form, then sprayed into a furnace where the powders become plastic but do not melt. The resulting blob is cold worked to form bars for machining. Powdered metal technology allows much higher amounts of alloying metals such as vanadium (which increases edge holding) than conventional blast furnace manufacture. The price of such special handling is significantly higher, but PM steels give extraordinarily longer tool life for metal cutting.
