Investigation of weld cracking in alloy 800

Journal Article · Thu Mar 01 04:00:00 EST 1984 · Weld. J. (Miami); (United States)

OSTI ID:6422582

Lippold, J C

The subscale Varestraint test has been used to determine the relative hot cracking susceptibility of the fusion zone in four commercial heats of alloy 800. Although all four heats were susceptible to cracking, one heat exhibited a significant increase in cracking relative to the other three. Optical metallography revealed that nearly all the cracking was localized along fusion zone grain boundaries. Microprobe analysis of the grain boundaries detected high concentrations of titanium, silicon, and niobium resulting from partitioning during solidification. The fusion zone hot cracking mechanism in alloy 800 involves the complex interaction of titanium, silicon, niobium, and carbon along the solidification boundaries. SEM and Auger analyses of the hot crack fracture surfaces revealed the presence of (Ti, Nb)-rich carbides, suggesting that these particles precipitate from the liquid which solidifies last on the fracture surface. 23 references.

• Research Organization: Sandia National Lab., Livermore, CA
• DOE Contract Number: AC04-76DP00789
• OSTI ID: 6422582
• Journal Information: Weld. J. (Miami); (United States), Journal Name: Weld. J. (Miami); (United States) Vol. 63; ISSN WEJUA
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360103* -- Metals & Alloys-- Mechanical Properties
ALLOYS
CHROMIUM ALLOYS
CRYSTAL STRUCTURE
DIAGRAMS
ELECTRON MICROSCOPY
ELEMENTS
FABRICATION
FRACTURE PROPERTIES
GRAIN BOUNDARIES
HEAT RESISTANT MATERIALS
HEAT RESISTING ALLOYS
INCOLOY 800
INCOLOY ALLOYS
IRON ALLOYS
IRON BASE ALLOYS
JOINING
MATERIALS
MECHANICAL PROPERTIES
METALS
MICROSCOPY
MICROSTRUCTURE
NICKEL ALLOYS
NIOBIUM
PHASE DIAGRAMS
PHASE TRANSFORMATIONS
SEMIMETALS
SILICON
SOLIDIFICATION
STRESS ANALYSIS
TITANIUM
TRANSITION ELEMENTS
WELDING