Microstructural Characterization and High Strain Rate Plastic Flow Behavior of SMAW Armox500T Steel Joints from Spherical Indentation Experiments

• Published in: Journal of materials engineering and performance 2018-08, Vol.27 (8), p.4261-4269
• Main Authors: Saxena, Ambuj, Kumaraswamy, A., Sethi, Sanghamitra, Madhusudhan Reddy, G., Madhu, Vemuri
• Format: Article
• Language: English
• Subjects: Characterization and Evaluation of Materials; Chemistry and Materials Science; Corrosion and Coatings; Engineering Design; Materials Science; Quality Control; Reliability; Safety and Risk; Tribology
• ISSN: 1059-9495; 1544-1024
• DOI: 10.1007/s11665-018-3487-3

Static indentation and uniaxial compression tests have been conducted on Armox500T steel and its weldments to predict the constraint factor (CF), i.e., ratio of Meyer’s hardness to uniaxial flow stress. Series of dynamic indentation experiments were carried out at impact velocities ranging from 5 to 300 m/s to estimate dynamic hardness as a function of average strain. Subsequently, dynamic indentation (DI) test data and CF determined under static indentation conditions have been used to study the high strain rate plastic flow behavior of Armox500T weldments in comparison with the base metal. It was observed that flow stress for Armox500T and its weldments under dynamic loading conditions (10 4  s −1 ) are significantly higher than flow stress measured under static loading conditions (10 −3  s −1 ). The plastic flow behavior computed from DI is in good agreement with the data evaluated through conventional split Hopkinson pressure bar technique. Further, the study of the microstructure of base metal and weldments by optical microscopy and SEM revealed a considerable variation in the microstructure.