Investigation of Weld Pool Structure and Property Control in Pulsed Arc Welding.

reportActive / Technical Report | Accession Number: ADA097392 | Open PDF

Abstract:

Pulsed current gas tungsten arc welds made in Fe-26Ni alloy and AISI 321 stainless steel were dimensionally and structurally analyzed. Weld pool kinetics, weld surface ripple formation and weld solidification structure were studied using high speed motion pictures, conventional and scanning electron metallography, and x-ray dispersive analysis. Varestraint tests were performed on AISI 321 and 316 stainless steel sheets to study the effects of grain refinement on the properties of the weld metal and its hot cracking tendency. A two-dimensional heat flow computer model, utilizing an explicit finite difference technique, was developed to predict temperature fields, thermal gradients, the solidus and the liquidus movement and weld pool size and shape at anytime during the course of the welding operation. Results indicate pulsed arc welding process can be manipulated to influence mixing in the weld pool, grain morphology and size in the solidified weld metal and its properties, i.e., hot cracking tendency. Computer simulations of the heat flow can provide accurate predictions of the thermal regime occurring at and around the weld pool during welding. Author

Author(s):
Ecer, G. M. ; Lessmann, G. G. ; Brody, H. D.
Author Organization(s):
WESTINGHOUSE RESEARCH AND DEVELOPMENT CENTER PITTSBURGH PA
Descriptive Note:
Final rept. 15 Sep 77-14 Sep 80,
Supplementary Note:
Prepared in cooperation with Pittsburg Univ., PA.
Pagination:
0126

Security Markings

DOCUMENT & CONTEXTUAL SUMMARY

Distribution:
Approved For Public Release

RECORD

Collection: TR
Identifying Numbers
Report Number(s):
81-9D4-PULSE-R1
Contract/Grant Number(s):
N00014-77-C-0596
 Subject Terms
Joint Capability Areas:
JCA_5_Command and Control; JCA_5.3_Planning; JCA_1.2.3_Educating; JCA_4.6_Engineering; JCA_5.3.3_Develop Strategy; JCA_5.3.4_Develop Courses of Action; JCA_5.3.5_Analyze Courses of Action; JCA_1.2.5_Lessons Learned; JCA_1.2.7_Experimentation; JCA_4_Logistics
Modernization Areas:
Quantum Science and Computing
Communities of Interest:
Weapons Technologies
Descriptor(s):
*CONTROL, *PROCESSING, *STAINLESS STEEL, *PULSES, *ARC WELDING, COMPUTERIZED SIMULATION, MODELS, MORPHOLOGY, SOLIDIFICATION, GASES, WELD METAL, WELDS, SURFACES, FINITE DIFFERENCE THEORY, TEMPERATURE GRADIENTS, REFINING, GRAIN STRUCTURES(METALLURGY)
Field(s)/Group(s):
Metallurgy and Metallography, Fabrication Metallurgy
Keyword(s):
Computer models, Weld pool structures
Report Date:
1981 Mar 04