Abstrakt

Effect of a plastic deformation in traction on the hardness, the thermal expansion and the corrosion behaviour of a ferritic steel

Sullivan De Sousa, Patrice Berthod, Jean-Pierre Philippe

A ferritic steel was obtained with different states of plastic deformation by traction test.Metallographic sampleswere prepared for opticalmicrostructure examination, Vickers indentation tests and corrosion tests in a sulphuric solutionwith electrochemicalmeasurements,while dilatometry runs between roomtemperature and 700°C were performed on parallelepipeds. Hardness becomes significantly high in the most strained zones, especially for surface parallel to the tensile deformation. Thermal expansion is slightly decreased by the plastic deformation and it looses the good linearity observed for the not strained samples. The corrosion rate, in the active state, is greatly enhanced by plastic deformation, as shown by the significant decrease in polarization resistance.