Metal finishing Q&As since 1989

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Chrome Plating of Work Rolls on Aluminium Cold Rolling Mills

We wish to improve the life of our Work Rolls on Aluminium Cold Rolling Mills and Aluminium Hot Rolling Mills. Is Chrome Plating the solution. Is Chrome Plating being used by others for this? Would it improve surface quality of Aluminium Sheet also?

Ashutosh Dixit
- Kanpur, Uttar Pradesh, India
2003

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Chromium will increase the wear life of cold rolling rolls. Hot rolling is not a good application as chrome begins to soften at about 300 °C. Chrome thickness is also a factor depending of causes for roll failure. If wear is the only problem 0.001-0.002" is OK, but if you have frequent accidents with cracks or spalls chrome could make it worst due to its tendency to greatly reduce fatigue strength and induce hydrogen embrittlement.

Guillermo Marrufo
Monterrey, NL, Mexico
2003

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Dear Sir,
The life of Work Rolls or the time between subsequent regrindings can be reduced by using Rolls of higher hardness and higher chrome composition in the material of the Rolls. The hardness should be as high as possible - preferably 65 HR'C'+.
Hardchrome plating would not help as the plated layer is very thin and would come out after every regrinding. Also it can lead to failure of Rolls due to Hydrogen embrittlement.

Regards,

Anand Vaid
- Delhi, India
2005