rust contamination of stainless steel: aluminum particles
rust contamination of stainless steel: aluminum particles
(OP)
When small iron/steel particles fall down on stainless steel parts, these particles will oxidise by presence of moisture. Iron oxides are created and in addition oxygen is prevented to enter the area and stainless steel becomes active. Contamination corrosion of stainless steel does occur.
My question: What if the small particles are not made of iron, but made of aluminium (or p.e. zinc)? What will happen? Will the same occur?
My question: What if the small particles are not made of iron, but made of aluminium (or p.e. zinc)? What will happen? Will the same occur?





RE: rust contamination of stainless steel: aluminum particles
cheers,
gr2vessels
RE: rust contamination of stainless steel: aluminum particles
At ambient temperatures there is minimla problem. However above 419C the diffusion rate of the zinc is mildly agressive. Above 750C the zinc diffuses into the austentic stainless steel forming a nickel-zinc intermetallic compound at the grain boundaries, the nickel depleted ferrite zones cause internal stresses to rise and a crack occurs... basically unzipping the structure.
Vita sine litteris mors est.
RE: rust contamination of stainless steel: aluminum particles
I thought that due to the difference in corrosion potential of zinc and aluminum with stainless steel AND in the presence of moisture galvanic corrosion will occur.
We grit blast aluminum parts and stainless steel parts in the same area. My concern is that the stainless steel parts may be contaminated by aluminum dust particles and then by condensation galvanic corrosion will corrosion?
RE: rust contamination of stainless steel: aluminum particles
Separate to galvanic effects, zinc on stainless is generally a no-no due to the embrittlement issue at high temperatures, but as Rich2001 said, at ambient temperature it's probably not a big issue.
RE: rust contamination of stainless steel: aluminum particles
As Rich-2000 has reported as: 'The Zinc- Stainless cracking as gr2vessels mentioned is called " Solid Metal Embrittlement"
Should that not be called as ' Liquid Metal Embrittlement' instead?
MetCorr