Sand Cast Aluminum Alloys For Explosion Proof Enclosure

[pdybeck]

I am looking for a Sand Cast Aluminum Alloy to be used for an explosion proof enclosure rated for Class 1 Div 1 areas, Groups A,B,C,&D. I am considering 356-T6, but am not satisfied with the strength. I would consider 771-T71 for obvious strength reasons, but I really don't know much about the material - Is it readily available, cost effective? I looked at using 201, and some other alloys that can be tempered to obtain the strength properties of 771-T7, but all the ones that I have found have a copper content greater than 4-5%. From my recollection, I need to have a material with a copper content less than 4% (Not positive on that number, but its in the ballpark), for explosion proof considerations. Could anyone recommend a sand cast aluminum material that has high strength characteristics, low copper content (if thats necessary for Class 1 Div 1), readily available from casting vendors, and cost effective? Your help would be greatly appreciated.

PDY

 

[TVP]

I am not familiar with enclosure proof ratings, so I don't know why copper content would be specified to be below a certain amount. For this application, if you want an aluminum casting with high strength and high toughness, then I would recommend 201.0 in either the T6 or T7 condition. Premium-quality, precision investment castings (ASTM B 618) can be produced essentially with zero internal defects (Class A, no gas porosity, no shrinkage porosity, etc.) that will yield consistently high mechanical properties.

 

[pdybeck]

Thanks for the reply, TVP. One more question - how available is 201 in the T6 or T7 temper. I am beginning the quoting process with a casting vendor and have developed a list of possible materials. Do you know anything about the availablity of 201 T6 & T7, as well as 204 T6, 206 T7, or 771 T71? Any help would be appreciated.

PDY

 

[TVP]

Sorry, I can't really answer this question for you. These are all commonly used alloys, but in different industries, different vendors, etc. I would recommend reviewing suppliers using the AFS website link below:

http://www.castingsource.com/