a mohassel - sharif university
a.h kokabi
p davami

the wide -gap aluminothermic rail welds with root opening of 50-70 mm were produced using the plain carbon steel rail and the non-alloy aluminothermic charge such process can repair the defective rails each with only one wide gap weld instead o fusing a relatively long plug rail and two standard welds. the corresponding equipment including the sand molds the crucible and the self -tapping thimble were designed mechanical properties and micro -structure of the welds and of the heat affected zone HAZ of the rails as well as the impact energies and the fracture toughness of the welds were investigated . the wide gap aluminothermic rail welds exhibited yield strength and tensile strength somewhat lower than those of the rail and the respective strengths of the HAZs failure happened in the weld center for a tensile specimen that included both the weld and the HAZ of the weldment.

wide-gap,aluminothermic weld ,rail ,toughness