[phantom8]

I had arranged a shop to custom-cut some 1.5mm thick 6061 Aluminium Sheets. When I received the aluminium sheets, they're all bend. The one you saw on the photo link below is around 270mm long. I suspect the shop was not using 6061 Aluminium. To my understand, 6061 Aluminium sheets would not bend like these. I think they're cheating on me. Am I correct?

https://imgur.com/bjAzDWn

[Jim Dawson]

Once the stress have been relieved in the sheet due to cutting it can bend. The grade of material really doesn't make any difference.

[peteeng]

Hi Phantom - What temper did you spec on order? You can request a copy of the purchase order or deliver docket for the material. I would not expect a 6061-T6 sheet to do this but any sheet product can do it. Plus its anodised? This too can warp the sheet as the cleaning process removes material and the anodising can tension the surface. Peter

[phantom8]

Thanks for the reply, guys! The custom-made 6061 Aluminium parts were delivered from China (Aliexpress). They told me I could choose from 1060, 5052, 6061 & 7075 and I picked 6061 material. They didn't mention anything about T6 and I didn't have the knowledge to ask.

I had made some similar 6061 Aluminium parts from another shop early this year. They didn't have this bending issue and were perfectly flat. They were also anodised in black. Seeing the outcome were so different and that's why I thought they cheated me.

[metalmayhem]

likely a mishandling issue