Abstract
Behaviours in tempering of high speed. tels quenched into hot bath. were investigated as to hardness. specific gravity, microstructure, dilatometric and specific resistance measurements.
Firstly, the change of hardness and specific gravity for hot bath quenched specimens followed by tempering were dealt with, Secondly, the tertiary Ar'' transformation revealed in 650°C tempering was described. Lastly a decomposition at 650°C tempering for but bath quenched specimens and their Ar'' traneformation were discussed.
