avoidance of disbonding in repair of large cast iron forming dies with powder welding

in a certain application concerning large forming dies disbonding after prolonged service i.e.impact of die with steel sheet sometimes when an area is welded for the second time has been reported due to the fact that the dies were extremely large and expensive it was decided to study the matter scientifically however the information available on the welding parameters used by the industry was very limited and samples of disbonded weld were not available there were two main theories one concerned cracking in serveice and the other concerned cracking during weld repair after simulating the situation in welding of the large dies on some small samples welding was done and microstructure of heat affected zone was studied two different powders which were available commercially were testedwith a wide range of welding parameters.

Keywords:

powder welding , ductile cast iron , HAZ , crack , weld zone