Abstract
In the preceding report, the authors described the effects of carbon, maganese and chromum on 5%Cr punching die steel. In the present investigation the authors studied the effects of W 1.0∼3.0%, Mo 0.5∼2.0% and V 0.25∼0.5% on the properties of die steels of standard composition C 1.1% and Cr 5.0%. The methods of experiment were the same as in the previous investigation. The results of the experiment are summarised as follows: (1) The A1 transformation point is not varied with the increase of W and Mo but the A1 point rises when the V content increases. (2) The quenching temperature necessary for the maximum hardness is lowered with the increase of the Mo content, but V shows the inverse result, while the temperature is not varied with a change in W content. (3) The tempering hardness increases with the increase of W, Mo and V. (4) The rate of deformation due to heat treatment decreases with the increase of the Mo and V contents but W shows the inverse result.
