Predictive Correlation Between Hardness and Tensile Properties of Submerged Arc Welded API X70 Steel
Ali Lahouel, Sameh Athmani, Amel Sedik, Adel Saoudi, Regis Barille, Lotfi Khezami, Ahlem Guesmi, Mamoun Fellah

TL;DR
This study shows that hardness measurements in welded API X70 steel can predict tensile properties, helping improve pipeline safety and weld quality.
Contribution
The paper introduces empirical models linking hardness and tensile properties in submerged arc welded API X70 steel.
Findings
Fusion zone hardness correlates strongly with tensile strength (R2 = 82%).
Base metal hardness significantly affects yield strength (R2 = 71%).
Hardness has a moderate negative correlation with elongation (R2 = 54%).
Abstract
This research investigates the statistical correlation between Vickers hardness and tensile properties of helical submerged arc welded high-strength low-alloy (HSLA) API X70 pipeline steel. Tensile tests were performed on cross-weld joints from 138 pipe specimens. Vickers hardness measurements were also conducted on 138 samples to evaluate the hardness distribution across the base metal, fusion zone, and heat-affected zone. Results show that the fusion zone exhibits the highest hardness, correlating with enhanced tensile strength (R2 = 82%). Linear regression models indicate that base metal hardness significantly influences yield strength (R2 = 71%), while moderate negative correlations exist with elongation (R2 = 54%). These findings suggest that hardness measurements can serve as a non-destructive predictive tool for tensile properties, improving weld quality and mechanical…
Genes, proteins, chemicals, diseases, species, mutations and cell lines named across the full text — each resolved to its canonical identifier and authoritative record.
Click any figure to enlarge with its caption.
Figure 1
Figure 2
Figure 3
Figure 4
Figure 5
Figure 6
Figure 7
Figure 8
Figure 9
Figure 10
Figure 11
Figure 12Peer Reviews
No public reviews on file for this paper yet. If you reviewed it on a platform where reviews are public (OpenReview, ICLR, NeurIPS, ICML), you can paste yours below so the community can read it here.
Videos
No videos yet. Explain this paper in a talk, walkthrough, or lecture? Add one.
Taxonomy
TopicsWelding Techniques and Residual Stresses · Hydrogen embrittlement and corrosion behaviors in metals · Microstructure and Mechanical Properties of Steels
