Effect of Dynamic Strain Aging on the Plastic Anisotropy and Mechanical Properties of Low-Carbon Phosphorus Steels

The effects of a dynamic-strain-aging treatment,as compared with a static-strain-aging treatment,on plastic anisotropy and mechanical properties has beendetermined for vacuum-melted low-carbon phosphorus steelscontaining various amounts of silicon. It was foundthat prestraining at 185°C, as compared with strainingat 22°C followed by aging for four hours at 100°C, resultedin about twice the increase in yield strength(90 versus 48 MPa) on subsequent tension testing at 22°Cand an improvement in r m values from about 1.8 to 2.0. Analyses of the textures and dislocation structuresof the steels after the two strain-aging treatments andafter subsequent deformation at 22°C showed that a greaterdislocation density gives rise to the greater strengtheningof dynamic-strain-aged specimens, and a finer polyhedralnetwork of dislocation tangles is believed to bethe reason for their higher rm values.