Oxygen effect on low-alloy steel weld metal properties

Journal Article · Sun Aug 01 00:00:00 EDT 1993 · Welding Journal (Miami); (United States)

OSTI ID:6327436

Potapov, N N ^[1]

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1. Scientific Industrial Corp., of Machinery Technology, Moscow (Russian Federation). Welding Dept.

It is shown that the weld metal oxygen content in submerged arc low-alloy steel welds, as well as in low-carbon steel welds is dependent on the concentration of oxides decomposed at low temperatures in a weld pool slag phase. The oxygen is mainly in the form of fine dispersed oxide inclusions of less than 0.03 [mu]m. Differentiated evaluation of silicon reduction effects in submerged arc welded low-alloy steels revealed that weld metal brittle fracture strength depends to a considerable degree on total weld metal oxide inclusion content than on silicon increment in the weld. Therefore, the increase of weld metal brittle fracture susceptibility with the growth of weld oxide inclusion content is important to know. Welds with lowered oxygen content [0] [<=] 0.02% also display the tendency to decrease in plasticity because (1) the ferritic-pearlitic matrix of improved purity is likely to generate unbalanced structures on cooling and, (2) when there are no oxide inclusions, the shape of sulfur and phosphor precipitation from the melt changes from globular to film-like. Optimal low-alloy steel weld metal oxygen content is defined in the range of 0.02-0.035.

• OSTI ID: 6327436
• Journal Information: Welding Journal (Miami); (United States), Vol. 72:8; ISSN 0043-2296
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
LOW ALLOY STEELS
SUBMERGED ARC WELDING
WELDED JOINTS
MECHANICAL PROPERTIES
FRACTURE PROPERTIES
INCLUSIONS
MICROSTRUCTURE
OXIDES
OXYGEN
PLASTICITY
ALLOYS
ARC WELDING
CHALCOGENIDES
ELEMENTS
FABRICATION
IRON ALLOYS
IRON BASE ALLOYS
JOINING
JOINTS
NONMETALS
OXYGEN COMPOUNDS
STEELS
WELDING
360103* - Metals &amp; Alloys- Mechanical Properties