Question 1

[trentar]

Hay!
I have a A351 CF8M cast steel which is full of tunder in the corners. I am aware that Hcl is not an appropriate acid but it removes the tinder away easier and mor eeffective as grinding which is not possible due to place problem (corners).

If I apply HCl with a brush for 5 Minutes and after remove itby cleaning it with water andd aölcaline cleaner I am able to remove tinder completely. Will this cause an issue to cast steel?

Thank you

 

[EdStainless]

It looks like there is a translation issue as I am not sure what 'tunder (or tinder)' is.
If you want to use acid to clean a stainless steel you should start with Nitric Acid. Room temp 30-40% concentration should have no impact on the metal at all.

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P.E. Metallurgy, consulting work welcomed

 

[mk3223]

Per your cleaning method with aölcaline cleaner, be aware that it may be a potential risk for the stainless steel to be corroded with the residual diluted HCL left on the surface.

 

[MJCronin]

Ed,

"Tunder" is a loud rumbling or crashing noise heard after a lightning flash due to the expansion of rapidly heated air.

"Tinder" is a cellphone dating app in which many participants are looking for casual sex

Glad to help out ....


MJCronin
Sr. Process Engineer

 

[trentar]

Hyy!

I didi mistake in writing I thought a layer which appear on the metal surface after it is heated and when metall atoms react with oxygen. mayebe a Mill scale.

After the surface will be treated with HCl we will clean it neutralise it as according to EIGA requirements.

 

[EdStainless]

If I was the customer I would prohibit the sue of HCl; on the parts. It will etch the surface and lower the pitting resistance of those areas. Nitric+HF is the correct way to remove oxide from the surface of these parts.

= = = = = = = = = = = = = = = = = = = =
P.E. Metallurgy, consulting work welcomed