NTL Record

Title Structure and Properties of Thermite Welds in Premium Rails
Record ID 50028
Personal Name
Creator
Schroeder, L. C.; Poirier, D. R.
Source 110p. in various pagings
Corporate Creator University of Arizona
Corporate
Contributor
John A. Volpe National Transportation Systems Center (U.S.); United States. Department of Transportation. Federal Railroad Administration. Office of Research and Development
Publisher United States. Department of Transportation. Federal Railroad Administration
Publication Date 19851201
Language English
Abstract Thermite welds were used to join combinations of premium rails and AREA Controlled Cooled Carbon rails (i.e., standard rails). The premium rails comprised head-hardened rails and CrMo, CrV and Cr alloy rails. A major objective was to determine the feasibility of joining premium rails to each other and to standard rails with the thermite welding process. The objective was met in that metallurgically sound welds were produced using either "standard" or "alloy" thermite charges. Other objectives were to determine mechanical properties and metallurgical structures of the weld-metal and of the heat-affected zones. The "alloy" weld-metal was stronger than "standard" weld metal but had less tensile ductility. Both types exhibit ductilities of only 2-6 percent reduction in area and impact energies of only 1.5-2.8 Joules at 20 deg C. Tensile and impact specimens, which straddled the region of minimum hardness at the outer edge of the heat affected zone, show tensile ductilities of 19-60 percent reduction in area and only 2.6-6.9 Joules for impact energy. In addition, temperature in the rail near the weld metal was measured as four of the welds were produced; in a fifth, temperatures in the weld metal, itself, were measured. Finally, residual stresses were determined, and their effect on fatigue strength of welded rail is discussed.
Rosap ID dot:11429
Rosap URL https://rosap.ntl.bts.gov/view/dot/11429
TRT Terms Railroad rails; Railroads; Welding; Alloy steel; Residual stress; Rail steel; Metallurgy; Thermit welding
Classification AGR - INFRASTRUCTURE - Railroads;
NTL - RAIL TRANSPORTATION - RAIL TRANSPORTATION
Geographical
Coverage
United States
Contract Number RR519/R5304
Report Number DOT/FRA/ORD-85/02; DOT-TSC-FRA-84-4
Resource type Tech Report
URL https://ntlrepository.blob.core.windows.net/lib/50000/50000/50028/DOT-TSC-FRA-84-4.pdf
Format PDF
Database NTL Digital Repository