5 replies to this topic

[sunnycali85d]

Hi guys,

 

I'm Max. I just signed up. I hope you guys are doing well.

 

I am trying to create basic geometries in 6061 aluminum metal - for the sake of understanding the process of metal molding. My project will later be directed towards 3D printing - but first I need to be able to SINTER aluminum - which is the process of heating it up to its melting point to allow the metal powder to fuse together. I hear it is very challenging to sinter aluminum so I have done some research and found the following thesis article which states the following:

 

"The present invention is based upon the inventor's Surprising discovery that heating aluminum powder in a nitrogen (N) atmosphere which contains a partial pressure of water vapor(HO),in the narrow range of about 0.01kPa to about0.02kPa,causes the aluminum powder to sinter together"

 

Now, I have access to a nitrogen furnace, however I don't know how to monitor and control the water vapor content in the nitrogen gas. Would anyone know how this person was able to monitor the water vapor content in the nitrogen gas? Or how this could be done today? This article is from 20 years ago.

 

If this is the wrong forum, I do apologize. Thank you for directing me to the right place

 

Max

[Pilesar]

Nitrogen gas is supplied dry. My guess is that the thesis author added a measured amount of water to the system to get the recipe that worked for him.

[sunnycali85d]

Thanks for your reply.

 

Is there no moisture in the tank - even in small amounts?

 

Assuming it is dry, any idea how we could mix water vapor with nitrogen? Especially in that small amount 0.004kpa?

[latexman]

You can buy custom blends of gases in cylinders.  It's done all the time for calibration of instruments.  Maybe, look into doing that.

[sunnycali85d]

That's a good idea. Where would you direct me to buy those special blends?

 

Is 0.004 kpa even measurable? Everything low pressure I find is in PSI and it's nowhere near able to measure that little.

[latexman]

In my little world it’s Praxair, Airgas, or Mesagas.