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POWDER METALLURGY TOOL STEEL
PM Steel for improved production economy
The powder metallurgy (PM) process is a rapid solidification process for the
manufacturing of high-speed steel and tool steel. This method eliminates the
problems which arise when steel solidifies in ingot moulds, such as local
variations in chemical composition and microstructure in the form of
segregations.
The PM steel is melted in the usual manner, but when it is tapped, the steel
is fragmented by high speed gas jets into a shower of steel droplets which
quickly solidify into powder. Each particle can be regarded as a tiny ingot,
free of segregations thanks to the rapid cooling. The tiny particles are then
compacted to form billets which can be fabricated by means of ordinary
methods such as forging and rolling to the desired dimensions.
The PM tool steel Uddeholm Vanadis 4 Extra, Uddeholm Vanadis 6,
Uddeholm Vanadis 10, Uddeholm Vanadis 23 and Uddeholm Elmax are
produced by a special PM process which gives a superclean tool steel, with
improved properties over standard PM steel, like better polishability,
toughness and bend strength. Uddeholm Vancron 40 is a nitrided PM steel
offering advantages like low friction, antigalling and good resistance against
adhesive wear and is an alternative to a surface coated PM steel in this
respect.
• Dimensional changes are reduced during hardening due to the absence of
segregations
• Tools made of PM steel feature a high and uniform level of performance
• PM steel permit sharper cutting edges on press tools
• PM steel are more ductile due to their lack of segregations
• The lack of segregations permits a more effective use of alloying elements
and higher levels of alloying elements can be used than previously was
possible with conventional steel
• Desirable characteristics such as abrasion resistance can be enhanced
without sacrificing other vital properties
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