STUDY OF ROLLING DIRECTION INFLUENCE ON DEFORMATION AND FRACTURE ENERGY OF THE CHARPY SPECIMENS
DOI:
https://doi.org/10.20535/2305-9001.2016.77.77713Keywords:
Charpy specimen, rolled direction, energy of deformation and fractureAbstract
Purpose. The object of this paper is to study the effect of rolling direction on energy characteristics from low-carbon steel St3. Design/methodology/approach. Charpy specimens impact tests are one of more simple and inexpensive method to determine the mechanical properties of materials. The results of these tests can be used to estimate the strength and durability of large-scale structures. Material properties obtained from tests depend on the direction of rolled steel from which they are derived. It is necessary to control the rolling direction of produced specimens to obtain conservative results. Findings. A series of Charpy specimens impact test from low-carbon steel were carried out in the temperature range of -50 ÷ +50ºС with control of rolling direction. The values of total energy of deformation and fracture and its components: energy of crack initiation, energy of ductile crack growth, brittle cracks energy and ductile rupture energy were determined. From the test results of three groups A, B, C of specimens, it was shown that at low temperatures the rolled direction has almost no effect on energy values. It was found, that ductile-brittle transition temperature for specimens cuted along the rolling direction (Group A) higher than for specimens of other two groups (B and C).References
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