THE EFFECT OF THE COMBINED IMPACT OF EXTRUSION AND SCREW PRESSING ON THE MECHANICAL PROPERTIES AND FRACTURE MECHANISM OF LOW CARBON STEELS AT LOW TEMPERATURES

The issues of deformation processing of low-carbon steel billets using combined impact of extrusion and screw pressing (ESP) are  considered. The results of low-temperature tensile tests of steel  samples are  presented. It is shown that the characteristics of strength and plasticity  (ductility) of steel subjected to ESP at lower test temperatures (213 K)  are higher than that at room temperature. A fractographic study of the  destruction mechanisms of the steel in as-received condition and after  ESP processing at room temperature and at a test temperature of 213 K revealed a ductile (viscous) character of the destruction mechanism with micro pits and pits present in all areas of the fracture surface.

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