Steps for Hardening of Tools as a Function of Time, Temperature, and Phase Transformation
After hot forming, tool steel usually is submitted to heat treatment processes that may be split into two major steps. The first step (shown last week) is done to produce a low-hardness condition. The second step involves this homogeneous microstructure being converted to a higher-hardness condition, usually by martensite formation during the hardening and tempering heat treatments.
In a graphical form, the graph shows the typical processing and heat treatment sequences for hardening of tool steels, as a function of time, temperature, and phase transformation.
The graph shows plots of temperature versus time showing sequence of operations required to produce tool steels. Hardening heat treatment. L, liquid; A, austenite; C, cementite; F, ferrite; Ms, temperature at which martensite starts to form on cooling; RT, room temperature.
Volume 4D, Heat Treating of Irons and Steels -> Heat Treating of Carbon and Low-Alloy Steels -> Introduction to Heat Treating of Tool Steels -> Heat Treatment Applied to Tool Steels
