Austenite reversion in 18% Ni maraging steel and its weldments

ABSTRACT

In the heat-treated condition, 18% Ni maraging steels have a microstructure of aged martensite and essentially no austenite. However, austenite can form if the material is overaged. This has been termed as austenite reversion, a subject which has received much attention, because it importantly influences properties and performance of the steel. Reversion of austenite in fusion zones of weld joints in these steels has also been widely studied. Because of microsegregation, austenite reversion in the fusion zone is accelerated. Reverted austenite in the fusion zone strongly influences the performance of the weld joints. The present review critically analyses the published work on austenite reversion and its effects on properties and performance, covering both base metal and weld joints.

KEYWORDS:

• 18% Ni maraging steels
• overaging
• reverted austenite
• microsegregation in fusion zone
• dendritic cell boundaries
• filler wire composition
• fatigue strength
• fracture toughness
• stress corrosion cracking

Disclosure statement

No potential conflict of interest was reported by the authors.

Correction Statement

This article has been corrected with minor changes. These changes do not impact the academic content of the article.