The quality of work roll of cold rolling mill directly affects the surface quality, pass rate and rolling operation rate of aluminum sheet. The quality requirements of the work roll are higher and higher, but the basic requirements are as following:

1. High roll hardness (95-100HSD) and uniformity (±1HSD);

2. Deep hardened layer depth(20-55mm, radius direction);

3. High wear resistance;

4. Good anti-stripping performance;

5. Excellent mechanical properties.

With the introduction and reformation of rolling mill, the application of new technology and new process, the development of new aluminium plate and the improvement of quality of aluminium sheet, the requirement of work roll performance has been individualized.

Material performance of work roll and support roll

At present, common material is Cr2（9Cr2Mo、86CrMoV7） 、Cr3（9Cr3Mo、

MC3、70Cr3Mo）、Cr5 series. They have different abrasive resistance and quenching degree. Different material and different technological parameters are adopted to reach different depth of hardened layer, so as to meet the requirements of different rolling mills.