AISI 8640 material standard
AISI 8640 material standard
(OP)
Hello all,
our customer demands casting made of steel AISI 8640, Q+T to 269-331 BHN. No other mechanical properties were demanded, and when we asked for them, the response was that "The hardness required is 269-331 BHN and the remaining as per standard AISI 8640".
I googled 50 pages, but except chemical composition there were no mechanical properties others than for bars, pipes..., and none matching 269-331 BHN.
My question is, is there AISI 8640 standard which contains mechanical properties matching demanded hardness?
I would like to buy it, but I dont like buying pig in a poke.
I apologize for maybe stupid question, but I am still a little bit confused about the connections between AISI, SAE, ASTM, ASM and others American organizations, standards and material designations.
Dalin
our customer demands casting made of steel AISI 8640, Q+T to 269-331 BHN. No other mechanical properties were demanded, and when we asked for them, the response was that "The hardness required is 269-331 BHN and the remaining as per standard AISI 8640".
I googled 50 pages, but except chemical composition there were no mechanical properties others than for bars, pipes..., and none matching 269-331 BHN.
My question is, is there AISI 8640 standard which contains mechanical properties matching demanded hardness?
I would like to buy it, but I dont like buying pig in a poke.
I apologize for maybe stupid question, but I am still a little bit confused about the connections between AISI, SAE, ASTM, ASM and others American organizations, standards and material designations.
Dalin





RE: AISI 8640 material standard
RE: AISI 8640 material standard
RE: AISI 8640 material standard
Cast microstructures have several impurities and coarse grains structure. I have had several such requests for casting in EN24 grade steel (NiCrMo steel). The hardness is specified and chemistry confirmed.
Can you describe the casting for the benefit of understanding.
I'm just one step away from being rich, all I need now is money.
( read somewhere on the internet)
RE: AISI 8640 material standard
Take a look at ASTM A732 chemical compositions, you may find something very close to 8640 there.
RE: AISI 8640 material standard
The non-specific requirement for determining the 269-331BHN also makes things very easy. This is a fairly modest strength level and should be easy to achieve with any type of casting using this material. Especially since the mechanical properties of the heat treated casting can be taken anywhere you choose.
RE: AISI 8640 material standard
The casting is about 3.8 tons with maximum wall thickness about 100 mm.
The calculated DI is between 66-161 mm, so I will go to upper range of chemistry.
With mass about 6t with risers and gating system I will do it on EAF, so chemistry is no problem.
As for ASTM A732, it looks like 14Q has similar chemical composition (except lower C contetnt) and can get to desired hardness range.
I suppose oil or salt quenching from 860°C and tempering at +/- 600°C. I will do trials on blocks before.
Dalin