ASTM B633 vs. F1941 - Correlate salt spray life

[renasis]

Hello,

If a screw has a Fe/Zn 5 Type III ASTM B633 plating, what does that equate to in ASTM F1941?

Thanks,

-ren

 

[CoryPad]

That equates to code Fe/Zn 5A, which would provide 6 hours to first appearance of white corrosion products, and 24 hours to first appearance of red corrosion products during neutral salt spray testing.

 

[renasis]

CoryPad,

Thanks for the response. Why wouldn't it be 5B? I believe B633 states 12 hrs before first sign of corrosion.

Thanks,

-ren

 

[TVP]

5B is a better fit than 5A, because the requirement for white corrosion would be 12 hours rather than 6.