Low-Temperature Impact-Strength of Ironpowder Bars

摘要

Bars were made of three types of iron powder (atomized, electrolytic and hydrogen-reduced mill scale), at two different sintering temperatures and several different compacting pressures. Charpy impact-strength was then measured on each variety of bar at -40 degrees); the values obtained ranged from 3/8 to 5 ft-lb. The impact-strength of both the atomized and the electrolytic iron-powder (but not the hydrogenreduced mill scale) increased as compacting pressure and sintering temperature increased. However, no value of impact-strength achieved is high enough for cannon components. Since this investigation does not show the characteristics of all metal powders, additional investigations should be made of heat-treated alloy-steel powders, more like gun steels. Such investigations are expected to show higher strength in both tensile and impact tests. (Author)