Low-temperature mechanical and magnetic properties of the reduced activation martensitic steel

Abstract

Mechanical and magnetic properties as well as their relationship in the reduced activation martensitic (RAM) steel were investigated in the temperature range from --90°C to 20°C. Charpy impact tests show that the ductile-to-brittle transition temperature (DBTT) of the RAM steel is about --60°C. Low-temperature tensile tests show that the yield strength, ultimate tensile strength and total elongation values increase as temperature decreases, indicating that the strength and plasticity below the DBTT are higher than those above the DBTT. The coercive field (H_C) in the scale of logarithm decreases linearly with the increasing temperature and the absolute value of the slope of lnH_C versus temperature above the DBTT is obviously larger than that below the DBTT, also confirmed in the T91 steel. The results indicate that the non-destructive magnetic measurement is a promising candidate method for the DBTT detection of ferromagnetic steels.

Keywords

reduced activation martensitic (RAM) steel / ductile-to-brittle transition temperature (DBTT) / mechanical property / magnetic property / non-destructive detection

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Acknowledgements

This work was financially supported by the National Natural Science Foundation of China (Grant Nos. 11274305, 11375230 and 11475216).

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2014 Higher Education Press and Springer-Verlag Berlin Heidelberg