POSCO Giga Steel Welding Featured in World-Renowned Journal 'Nature'

POSCO's high-performance, low-cost gigasteel welding technology has been published in a world-renowned academic journal.

POSCO announced on the 13th that its gigasteel welding technology 'PosZET® GIGA' was featured in the December 12th issue of the comprehensive science journal Nature Communications.

Schematic diagram of the newly discovered mechanism of microstructure formation in gigasteel weld metal by the joint research team of POSCO and Changwon National University (Photo by POSCO)

POSCO's ultra-high-strength steel sheet 'Gigasteel' has a tensile strength of over 980 MPa, making it lightweight yet strong, and it has been used as a material for automobiles.

Materials for gigasteel welding have mainly used a large amount of nickel (Ni), but 'PosZET® GIGA' uses an optimal ratio of niobium (Nb) and chromium (Cr) instead of nickel as the welding material (wire). The microstructure of the weld metal at the joint is made into a complex and dense network-like structure, which simultaneously enhances strength and toughness.

By applying this technology, the bending fatigue strength of the joint increases by more than twice compared to existing methods, and the impact toughness improves by about 15%. When applied to automobile parts manufacturing, the joints can better withstand repetitive impacts and temperature changes without easily cracking, contributing to improved vehicle safety.

With improved performance of the welded area, the thickness of the steel sheet can be reduced, which is expected to contribute to lightweight vehicle design. Additionally, compared to the conventional method mainly using nickel, the cost is reduced by about half.

POSCO, in collaboration with Changwon National University, was the first in the world to metallurgically identify this technology. They revealed the atomic-level effects of the combined addition of niobium and chromium on the microstructure of the weld metal.

A POSCO official stated, "We recently received technology application approval from global automakers and plan to utilize it in actual automobile parts production," adding, "We intend to continuously expand sales of gigasteel using this technology in the future."

This content was produced with the assistance of AI translation services.