Welding and weldability of ductile intermetallic alloys. [(Fe,Ni)/sub 3/(V,Ti); (Fe,Co)/sub 3/(V,Ti)]

Conference · Thu Jan 01 00:00:00 EST 1987

OSTI ID:6095247

David, S A; Santella, M L; Goodwin, G M

Successful welds have been produced in several nickel aluminide (Ni/sub 3/Al) alloys. Weldability has been found to be a strong function of boron, other alloying additions, and welding speed. Cracking during welding observed in some of the aluminides was predominantly in the heat-affected zone (HAZ) and was always intergranular. Additions of iron promote the formation of a second phase. The observed HAZ cracking in some of these alloys resulted from thermal stresses imposed on this region of the weldment at elevated temperature and from grain boundary weakness. Sound welds were produced in sheets of (Fe,Ni)/sub 3/(V,Ti) and (Fe,Co)/sub 3/(V,Ti) ordered alloys. Welds of (Fe,Ni)/sub 3/(V,Ti) were disordered, but the tensile properties were not adversely affected. A reordering heat treatment restored the weldment properties to those of the base metal. Welds of (Fe,Co)/sub 3/(V,Ti) remained ordered after the weld thermal cycle. Factors that seem to influence the weldment properties include ordered domain size and precipitation of carbide. 23 refs., 8 figs., 24 tabs.

• Research Organization: Oak Ridge National Lab., TN (USA)
• DOE Contract Number: AC05-84OR21400
• OSTI ID: 6095247
• Report Number(s): CONF-870981-2; ON: DE87014061
• Resource Relation: Conference: Annual North American welding research seminar, Columbus, OH, USA, 29 Sep 1987; Other Information: Portions of this document are illegible in microfiche products
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ALUMINIUM ALLOYS
WELDABILITY
COBALT BASE ALLOYS
IRON ALLOYS
NICKEL BASE ALLOYS
TITANIUM ALLOYS
VANADIUM ALLOYS
BORON ADDITIONS
CRACKS
CRITICAL TEMPERATURE
GRAIN BOUNDARIES
HEAT AFFECTED ZONE
HEAT TREATMENTS
INTERMETALLIC COMPOUNDS
MICROHARDNESS
MICROSTRUCTURE
TENSILE PROPERTIES
THERMAL STRESSES
WELDED JOINTS
ALLOYS
BORON ALLOYS
COBALT ALLOYS
CRYSTAL STRUCTURE
HARDNESS
JOINTS
MECHANICAL PROPERTIES
NICKEL ALLOYS
PHYSICAL PROPERTIES
STRESSES
THERMODYNAMIC PROPERTIES
TRANSITION TEMPERATURE
ZONES
360101* - Metals & Alloys- Preparation & Fabrication
360103 - Metals & Alloys- Mechanical Properties
360102 - Metals & Alloys- Structure & Phase Studies