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Tensile Properties of Commercially Pure, High-Purity and Ultra-High-Purity Iron: Results of an International Round-Robin



Enrico Lucon, Kenji Abiko, Marlies Lambrecht, Birgit Rehmer


The room temperature tensile properties of iron with different purity levels (commercially pure, high-purity, and ultra-high-purity) were characterized at different strain rates in the framework of an international Round-Robin involving four laboratories (BAM, IMR-TU, NIST, and SCK•CEN). The test results were collected and analyzed by NIST, and are presented in this Technical Note. Data from all the participating laboratories were found in good agreement, thus allowing a clear assessment of the influence of strain rate and purity level on the tensile properties (mechanical resistance and ductility). A clear increase of yield strength and, to a lesser extent, of tensile strength was observed for all materials as the strain rate increases and the purity level decreases. The highest strain rate sensitivity was associated with the highest purity level (ultra-high-purity Fe). Ductility trends were less unequivocal, but typically an increase of elongation of fracture and reduction of area was detected as strain rate and purity level increase. Significant differences in tensile properties were observed between the two investigated types of high-purity Fe, indicating a notable influence of the production process in terms of melting environment (atmosphere and crucible).
Technical Note (NIST TN) - 1879
Report Number


Commercially pure iron, ductility, high-purity iron, purity level, Round-Robin, strain rate, tensile strength, ultra-high-purity iron, yield strength.


Lucon, E. , Abiko, K. , Lambrecht, M. and Rehmer, B. (2015), Tensile Properties of Commercially Pure, High-Purity and Ultra-High-Purity Iron: Results of an International Round-Robin, Technical Note (NIST TN), National Institute of Standards and Technology, Gaithersburg, MD, [online], (Accessed April 18, 2024)
Created April 1, 2015, Updated November 10, 2018