| 摘要 |
PURPOSE: To prevent generation of weld crack and to increase welding speed by rapidly induction heating weld zone to a specified temp. and making cementite crystallized at the time of welding graphite. CONSTITUTION: In welding of gray cast iron, a weld zone is subjected to rapid induction heating to a temp. of >=1000 deg.C to < the melting temp., the cementite crystallized at welding is made graphite. In executing this welding, the composition of welding bar contains Fe-Si or Ni-Si as essential component and 2-8% Si, or Fe-M as essential component and 6-20% M. By this method, the weld zone has the structure of gray cast iron without deterioration of mechanical property in weld zone and has the same material as that of base metal. Thus, automatic welding is enabled and welding speed can be made faster. |
