DB TEMA, Copyright FIZ Technik.
AN M98022006 640; Update: 19980318.
MJ Schiene; Thermitschweissen; Eigenspannung; Neutronen.
TI Residual stresses in alumino-thermic welded rails.
TC E Experimentelle Abhandlung.
AB Neutron  strain  scanning  has  been  used to map the residual stress
   field  that is generated in a railway rail by a standard gap alumino-
   thermic   weld   made   using  routinely  specified  procedures.  The
   longitudinal and vertical residual stress fields in the sections well
   away  from  the weld are characteristic of many unwelded rails, being
   generally  tensile in the head and foot with balancing compression in
   the web. In the vicinity of the weld the residual stress patterns are
   very  different.  At  the  top  and  bottom  surfaces of the rail the
   longitudinal  residual stress field is strongly compressive, which is
   generally  beneficial in that it would tend to inhibit the initiation
   and  propagation  of fatigue cracks from surface defects. Just at the
   surface   the   vertical  residual  stress  attenuates  to  zero  but
   internally,  in  the  web  region,  both  longitudinal  and  vertical
   components  of  the residual stress field are strongly tensile, which
   increases  the  susceptibility of that region to crack initiation and
   propagation   from   internal   material  defects.  This  pattern  is
   consistent with practical operating experience, which is that most of
   the small proportion of alumino-thermic welds that do fail do so as a
   result  of  porosity  or inclusions in the weld. It is found that the
   'boundaries'  of  the  'weld  type'  residual  stress  fields  do not
   coincide  with  the  boundary  of  the weld, nor of the heat-affected
   zone,  but  correlate  reasonably  well  with  the  positions  of the
   extremities  of  the  mould  assembly  and  with  the location of the
   steepest longitudinal temperature gradients.
AU Webster-P-J; Mills-G; Wang-X-D; Kang-W-P; Holden-T-M.
IN Univ. of Salford, GB; Chalk River Lab., Ontario, CDN.
SO Zeitschriftenaufsatz:  Journal  of  Strain  Analysis  for Engineering
   Design,  Band 32 (1997) Heft 6, Seite 389-400 (12 Seiten, 9 Bilder, 2
   Tabellen, 11 Quellen).
LG EN English.
AV TIB-ZN1347/LferZ322.
CC 3BB  *Mechanik von Festkoerpern, Fluessigkeiten, Gasen*
   3IGX *zerstoerungsfreie Pruefung von Werkstoffen/Bauteilen*
   3LNB *Schweissen, Loeten*.
MN EISENBAHNSCHIENE;  STOSS:SCHIENE;  SCHMELZSCHWEISSEN;  EIGENSPANNUNG;
   NEUTRONENSTRAHL;                 ZERSTOERUNGSFREIE-WERKSTOFFPRUEFUNG;
   thermitverfahren.
YR 1997.
ED 199804.
PT JL Long journal article.
TP 4613 J-of-Strain-Anal-f-Engng-Des.
IR IN=Univ-of-Salford; IN=Chalk-River-Lab.