D1.2 4.12.3 "Plasma or Laser Cut Edges"

Date 05-24-2023 18:11 Edited 05-25-2023 13:02

I tried searching and only found posts related to cleaning and edge prep but I was wondering if anyone could share some insight on the paragraph in D1.2 FABRICATION 4.12.3 "[for heat-treatable aluminum alloys, 1/8" of material shall be removed by machining from plasma arc and laser cut edges that will be welded]"

I'm assuming this is related to material metallurgy and the HAZ during the cutting process. Has anyone run into problems with laser cut parts? I totally could see issues from torch and plasma cuts, but a powerful fiber laser with modern tech and the cutting gasses they run at such fast cut speeds i doubt the material even has a chance to get warm.

EDIT:
further research shows this clause was added in the 2008 edition and also included 2 long paragraphs about surface roughness of the edges. this was subsequently removed in 2014.
My guess is back in early 2000's laser technology wasn't as advanced and Fiber lasers weren't a thing yet. several research papers discuss the differences and advantages specifically how the different wavelengths and optics play a part in minimizing haz and improving cut quality.
https://www.sciencedirect.com/science/article/abs/pii/S0030399222005527

I guess the reason for my post was more about why its still in the code and if there's good cause to bring up the idea of modifying that clause.
thanks

By 803056

Date 05-25-2023 11:32

Try placing your hand on it directly after cutting. Cool to the touch? Quenching.

Al

By SeeJeepGo (*)

Date 05-25-2023 12:21

I'm not the one doing the cutting. We ordered 150 brackets cut and bent from a third party mfg.

By jwright650 (*****)

Date 05-25-2023 19:56

I'm amazed at the latest cutting tech......I've been thrown a piece directly from the table and when I caught it, there was barely any heat in it at all.

By TimGary (****)

Date 05-26-2023 11:24

Out of curiosity, I looked for any interpretations or technical inquiries concerning this requirement from or to the D1.2 Technical Committee. For some reason, I see none of the above info or any documented correspondence to/from the D1.2 Committee in the AWS website.
It might take a while to get an answer, but why not send in a technical inquiry?

Tim

By SeeJeepGo (*)

Date 05-26-2023 11:52

I looked on the https://www.aws.org/standards/page/interpretations page and agree there is nothing listed under D1.2

i've never done a technical inquiry so i guess ill investigate that process.

thanks

By TimGary (****)

Date 05-26-2023 12:10

It's also interesting that the TACOM Ground Combat Vehicle Welding Code - Aluminum, which is basically a copy of AWS D1.2, does not have this particular requirement for removal of thermally cut edges, unless in regard to surface roughness.

Tim

By 803056

Date 05-31-2023 15:53

I wouldn't expect any degradation of the aluminum along the cut surfaces to be significant. The heat treatable alloys might experience some quenching without aging. The nonheat treatable might see some softening, but in either case, the material affected would be minimal.

Just my thoughts - Al