Differential thermal analysis in the study of weld metal solidification and hot cracking
Hot cracking, or solidification cracking, is one of the most extensively studied phenomenon in welding metallurgy. The efforts made to identify the causes of this type of cracking have been driven by the negative commercial and engineering consequences resulting from the formation of these defects. Through judicious weld joint design, the mechanical restraint can be minimized, but it can never be entirely eliminated simply because metals expand and contract when heated and cooled, respectively. The localized nature of heat input in fusion welding insures a non-homogeneous thermal field being applied to the parts being welded, resulting in the development of strains in the as-solidifying weld metal. With the inherent limitations on the mechanical restraint factor, much research has gone into identifying those alloy compositions which minimize the microstructural factor required for hot cracking to occur. Examples from the author's own research are presented as a tutorial to show how differential thermal analysis techniques have been used to study the chemical/microstructural factors associated with solidification and fusion zone hot cracking in nickel based engineering alloys. References to other uses of these techniques in related welding metallurgy studies are also given.
- Research Organization:
- Sandia National Labs., Albuquerque, NM (United States)
- Sponsoring Organization:
- DOE; USDOE, Washington, DC (United States)
- DOE Contract Number:
- AC04-76DP00789
- OSTI ID:
- 5715320
- Report Number(s):
- SAND-92-0283C; CONF-911003--23; ON: DE92008681
- Country of Publication:
- United States
- Language:
- English
Similar Records
The solidification and welding metallurgy of galling-resistant stainless steels
Using backscattered electron diffraction to understand weldability
Related Subjects
360101* -- Metals & Alloys-- Preparation & Fabrication
360103 -- Metals & Alloys-- Mechanical Properties
ALLOY-NI53CR19FE19NB5MO3
ALLOY-NI54MO17CR16FE6W4
ALLOY-NI61CR22MO9NB4FE3
ALLOYS
ALUMINIUM ADDITIONS
ALUMINIUM ALLOYS
CHROMIUM ALLOYS
COBALT ALLOYS
CORROSION RESISTANT ALLOYS
CRACK PROPAGATION
DIFFERENTIAL THERMAL ANALYSIS
HASTELLOY C
HASTELLOYS
HEAT RESISTANT MATERIALS
HEAT RESISTING ALLOYS
INCONEL 625
INCONEL 718
INCONEL ALLOYS
IRON ALLOYS
JOINTS
MATERIALS
MOLYBDENUM ALLOYS
NICKEL ALLOYS
NICKEL BASE ALLOYS
NIOBIUM A
NIOBIUM AL
PHASE TRANSFORMATIONS
SOLIDIFICATION
THERMAL ANALYSIS
TUNGSTEN ALLOYS
VA
VANADIUM ADDITIONS
WELDED JOINTS