aluminizing 304

[harbs]

i have been searching for a typical diffusion coefficient for an aluminium powder into 304 SS can anyone help?

 

[metengr]

You can try the following assumption;

304ss, iron-base alloy, therefore the diffusion coefficient will be influenced predominantly by iron versus other alloying elements like Cr and Ni. In reality, the diffusion coefficient for Al in 304ss will be influenced by solute alloy additions like Cr and Ni – however, this becomes very complicated in dealing with ternary diffusion coefficients.

The diffusion coefficient for Al in iron ranges from

4 x 10^-9 to 3 x 10^-8 cm^2/sec for temperatures 875 deg C to 1100 deg C

Source; Transport Phenomena in Materials Processing

 

[unclesyd]

All the diffusion process that use powdered Al had to use a catalyst.

I was trying to locate Alon Technologies but they went under and bought by Group Ultra, Houston no further information. There are a lot of papers around but they are hard find in all the commercial stuff popping up in search

Here is all the information that I have at the present.

http://www.diffusion-alloys.com/index.htm

http://www.babcock.com/pgg/ps/boilertreatments.htm

 

[EdStainless]

The Ni seriously slows the diffusion. This is even true for Nitrogen. I wouldn't expect to get anywhere close to the Al/Fe values.

= = = = = = = = = = = = = = = = = = = =
Corrosion never sleeps, but it can be managed.

http://www.trenttube.com/Trent/tech_form.htm