gdodd
Automotive
- Jul 18, 2001
- 138
Ductile Iron Problem
We have found a cast iron part containing areas of flake graphite but mostly compacted graphite and spheroidal graphite where normally it would be 100% spheroidal graphite in a ferrite matrix. Understandably the properties such as hardness and ductility have been reduced dramaticly.
The part comes from a batch which had been checked for magnesium during casting (0.45%) and all remaining elements analysed indicate cast batch conforms to specification. As yet the affected part has not been analysed.
During cast ing the molten iron is poured from a ladle into a spoon which bottom pours into the mould containing two cavities.
According to records the iron conforms to specification before it is poured into the spoon.
Is there any way the refractory lining, coke cans or other contaminant could cause magnesium depletion between exiting the pouring ladle to entering the mould?
The problem does not appear to have affected the remaining batch code of 1200 castings.
Thanks in advance
We have found a cast iron part containing areas of flake graphite but mostly compacted graphite and spheroidal graphite where normally it would be 100% spheroidal graphite in a ferrite matrix. Understandably the properties such as hardness and ductility have been reduced dramaticly.
The part comes from a batch which had been checked for magnesium during casting (0.45%) and all remaining elements analysed indicate cast batch conforms to specification. As yet the affected part has not been analysed.
During cast ing the molten iron is poured from a ladle into a spoon which bottom pours into the mould containing two cavities.
According to records the iron conforms to specification before it is poured into the spoon.
Is there any way the refractory lining, coke cans or other contaminant could cause magnesium depletion between exiting the pouring ladle to entering the mould?
The problem does not appear to have affected the remaining batch code of 1200 castings.
Thanks in advance
