Test specimen for preferential weld attack

[rustbuster]

Hello all, I am seeking a metallurical lab / company in the Houston area who could assist me with the following.

I need to preferentially corrode a mock up A516-70 welded specimen in the weld zone to given depths. (Mechanical means not acceptable)The piece will be 0.75" thick and I would like to corrode areas of the weld to 10% 20% 30% 50% wall loss increments to qualify an advanced NDE Technique for a specific damage mechanism.

Suggestions greatly appreciated.

 

[Hush]

The Southwest Research Institute

http://www.swri.edu

in San Antonio might be worth a try.

 

[rustbuster1]

This isn't so difficult. You can mask the various zones for different times and expose the sample in HCl or similar acid to get the corrosion-type trenches you seem to need. The electroplating folks have good masking paints. etc. You can start with the whole area masked except where you want the deepest ditch, then remove the masking where you want the next deepest ditch, etc., exposing the steel for different times and controlling the depths.
Alternatively you could make some mechanical grooves of different depths and then expose the whole weld zone to acid to get the rough-etched surface you may be looking for.

My company has its main metallurgical lab in Austin if you are interested.

 

[rustbuster]

Thank you for the tips. I may have someone to do electrochemical machining(EDM). Had thought of masking and HCl, but havenet found a lab to do it. If the EDM falls through I'll get the Austin Contact.

Regards