how to diffrentiate between grey and ductile cast iron?
how to diffrentiate between grey and ductile cast iron?
(OP)
hi all
how can I diffrentiate between grey and ductile cast iron with its apperance.
how can I diffrentiate between grey and ductile cast iron with its apperance.





RE: how to diffrentiate between grey and ductile cast iron?
What is your situation that requires this comparison? There could be other options.
RE: how to diffrentiate between grey and ductile cast iron?
RE: how to diffrentiate between grey and ductile cast iron?
Take a small sharp chisel and get on an edge and try to peel off a small chip.
The gray iron will not make a chip of any sorts while the ductile iron will try to make a chip.
RE: how to diffrentiate between grey and ductile cast iron?
In deep suspense
RE: how to diffrentiate between grey and ductile cast iron?
The ductile iron will try to make a small curl, i.e. ductile.
The GI will be very small chips/pieces more like a dust, i.e. brittle.
Malleable will act similar to ductile iron.
Nodular iron will act the same ductile iron.
White iron will probably break the chisel.
Wrought, puddled, or charcoal iron will make a half curl.
Semi-steel will make a full curl.
I should have added that small chisel with a single bevel and the chisel inclined at 30-40 degree angle against the material in question works best.
RE: how to diffrentiate between grey and ductile cast iron?
RE: how to diffrentiate between grey and ductile cast iron?
RE: how to diffrentiate between grey and ductile cast iron?
Semi-steel is a generally a cast iron that has a high percentage of steel scrap added. The higher the percentage steel scrap the more ductile the material is.
My statement on semi-steel probably isn't true for all cases as the material we bought was quite ductile so a general statement would be that it will act similar to ductile iron.
RE: how to diffrentiate between grey and ductile cast iron?
The experience of your shop personnel is correct. This simple test can distinguish the defective ingot moulds from the good ones. I used this test 25 years ago while inspecting ingot moulds . If there are any severe internal flaws you just get a thud,discard those. By practice one can start identifying defective moulds. I do not know if there are any standards for this test .
Another interesting way of identification for ductile iron. A freshly fractured sample is smelled and tasted!! Characteristic Mg smell will indicate if treatment is complete and nodularity. This is a typical shop practice and I too have learnt it.
RE: how to diffrentiate between grey and ductile cast iron?
Bill
SBI
Central Ne.,USA
RE: how to diffrentiate between grey and ductile cast iron?
RE: how to diffrentiate between grey and ductile cast iron?
RE: how to diffrentiate between grey and ductile cast iron?
I have seen this used on cast iron and also on bricks. A variation in density (for a sintered material) or damping characteristics (cast iron) will give you a different number.
If your parts (or molds) are all the same size then you can compare readings taken in different locations and directions.
We also made some white cast iron items and it could easily pick out the ones that were not fully 'white'.
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Corrosion never sleeps, but it can be managed.
http://www.trenttube.com/Trent/tech_form.htm
RE: how to diffrentiate between grey and ductile cast iron?
RE: how to diffrentiate between grey and ductile cast iron?
The ring test is a good easy and cheap way to check. as to why one might ring and another might not, any number of things come to mind: insufficient mixing of the molten iron during casting, gas inclusions, differences in cooling rates, incorrect alloy used. I'm sure there are probably others that don't immediately come to mind.
RE: how to diffrentiate between grey and ductile cast iron?
RE: how to diffrentiate between grey and ductile cast iron?