This is shown on fig 1. After this the test piece was mounted in the Vickers hardness The key to good hardenability is controlling the ferrite transformation from austenite and to do this it is necessary to produce large austenite grains.
Taking safety in to consideration it should be noted that the test piece should not be handled until the whole test piece has cooled down. This makes the metal extremely hard and might even make the metal crack.
This will be done by using the Jominy end quench test on each of the test pieces and then testing the hardness of the particular steel from the quenched end, to the end of the test piece. The results were then tabulated see fig 1.
Procedure Three test pieces EN 8, EN 16 and EN 24 were heated above their A3 temperature to create a homogeneous austenitic structure and then end quenched by means of water at C.
Procedure Three test pieces EN 8, EN 16 and EN 24 were heated above their A3 temperature to create a homogeneous austenitic structure and then end quenched by means of water at C. Also when the microstructure of the metal is in austenite form, that is to say it is face centred cubic, the carbon is absorbed more as the interstitial gaps are bigger and so when it is quenched it traps the carbon by giving it no time to precipitate out of the metal when it transforms to body centred cubic.