Poor Aluminum quality

Hey all, I know that back in 2015 there was a thread about the same thing here https://www.practicalmachinist.com/...-issues/poor-quality-aluminum-sources-301732/ but I feel like it’s time for a little update, 2022/COVID/supply chain edition.

Our shop was waiting on getting aluminum for months and when it finally came in, it was time to make some parts. Cut a whole bar of 6061 T6 and tried to run some parts. We have a 9/16-20 tap and 10-32 tap in our program and for the first time in 4-5 years we’ve been having issues with tapping. The tap gets stuck or breaks off. The 9/16 tap took hefty tap wrenches to get out and the part was scrapped every time. Some parts made it out with no issues on tapping, but 95% of the time it was destroyed.

That night I started looking on these forums to try and diagnose these tapping issues and I came across that thread I linked earlier and everything started to come together. The next morning I come into work and sure enough, The 6061 came from Service Center, everyone’s worst enemy when it came to crappy aluminum. I’ve had to modify the program to give time to oil up the hole and the tap manually (something I should have done much sooner I admit) and now it runs like a dream. But regardless, this should have never been a problem in the first place. Out of an entire bar, more than half turned into scrap.

We have other bars here too, 7075 T6 from Taiwan Ye Fong, and a smaller 6061 T6 bar from SA ASTM. Does anybody have any experience with these places?

Our distributor, coast aluminum normally sends us Kaiser stuff and we’ve never had a problem with them. Honestly considering all of the manufacturing/supply chain issues in the world, I have a hard time being upset at coast; I can only imagine that they got us what was available. 5 years and no issue with metal, and this one time it changes it’s all garbage material

I've run plenty of 7/8 dia 2024 T351 Ye Fong in the past. Was very good material. Just as good as Kaiser or Alcoa.

Just tell Coast you don't want any material from Service Center. I've had issues with Service Center material in the past, but nothing as bad as you describe. Sometimes Service Center is the only choice for thick-section flat bar.

Regards.

Mike

If you saved any of the SC 6061, send a sample to your supplier and ask them to check it for hardness. At least in my experience one reason for 6061 behaving "gummy" and locking on taps is poor heat treat and resultant lower than spec hardness.

Obviously if you have a tester there do your own check and compare it to a "known good" piece of 6061.

Is the issue only with cut taps? I haven't had any issues with SCM specifically, but we try to form tap anywhere possible in softer materials.

I mainly run rounds ranging from 1" to 6"........................Kaiser 6061 has been garbage for the last few years.............stringy, gummy, can't break a decent chip...............it used to be my go to..................now I went back to Hydro...............seemed OK until just this last month. I don't think I have ever went through so many small ID groove inserts....................few thousand parts with O ring and seal grooves outa some 1.875"Ø............inserts would bind up in grooves and randomly snap off...................tried everything. Different groove cycles to break chips, re-ran the drill to clear chips, upped coolant concentration, ground in chip breakers, etc, etc, etc............ Normally I can get one insert to last 3-4000 parts..............in on 1500 pcs job I prolly used 6-7 inserts and 3-4 solid carbide ID groove tools.........................Few weeks prior I rand around 3000 parts in 2.250"Ø Hydro..................ran fine. One ID groove insert..........................and SCM................I really don't like it, but I'll run it in simple turn/bored parts...................

A fee years back, I was making a lot of aluminum pistons for hydraulic cylinders.
My customer was supplying the material.
It came from a local place that I never would buy material from.
Almost half of the material had hard spots & 'inclusions' in it.
I would be drilling for boring amd find a hard chunk.. Sometimes is looked like gravel or staged, and sometimes a piece of glass.
The supplier would replace material only.
After I kept charging them extra labor, they started letting me get the material.
Is seems like I was buying from Jorgenson and Lokey Metals.
They always sent Kaiser or Alcoa.
That local place said theirs was an Asian brand ( Chinese I guess).

That's not true at all.

Republic pours 12L, and you can buy it direct from Republic, or I think that Corey uses some Republic HR as well.
Republic's stock link shows that they have .5" through 3" CDR 12L14 in stock at their Massilon, Ohio facility.
(there are a few holes in there with empty shelves waiting for the next pour, but ...)

Corey also uses some HR from the UK that is good stuff.
I ass_u_me that it is the same HR supplier that Barren Drawn Steel use'ta use back in the day, and theirs was WAY better than common 12L.
On a hex job, I found that my Barren material - on a form tool lasted 2wiced as long, and a form tap lasted up to 4 times as long.

I think that Niagara Lassale also pours 12L, but would have to dbl check that to be sure.
Yes, I just checked their line card, and it lists 12L for sure.



----------------------

Think Snow Eh!
Ox

I was talking with a head guy at a metal supplier about this issue as I have had problems bending 5052 as well sometimes. Always with grain, not against.

Don't quote me on this, but I'm looking to see how true this is.

I was told that due to supply issues currently happening for the last 1.5 years, companies have been pulling "old" (few years old as "national stock") and the alum can be age or work hardening just sitting there. So your getting material with heavier oxides and such on newly purchased material.

I was told something like Vietnam or taiwan or something like that has like 20 million pounds that were already years old that are being sold as new stock.

Sent from my SM-G960U using Tapatalk

Sorry to hear about Service Center, the last batch I got from them a couple hundred pounds of 1.5" diameter machined pretty well. I was hoping their quality had improved, I guess not. Be aware also sometimes long trusted tool brands will have a drop in quality, but we are talking tapping aluminum here.

Just how much steel available today doo you think is virgin?

Alum would have a MUCH better likelyhood of being virgin that steel.
But that would likely be limited to material coming in from Russia and there abouts - via Iceland.


----------------------

Think Snow Eh!
Ox

Bondo said:

I was talking with a head guy at a metal supplier about this issue as I have had problems bending 5052 as well sometimes. Always with grain, not against.

Don't quote me on this, but I'm looking to see how true this is.

I was told that due to supply issues currently happening for the last 1.5 years, companies have been pulling "old" (few years old as "national stock") and the alum can be age or work hardening just sitting there. So your getting material with heavier oxides and such on newly purchased material.

I was told something like Vietnam or taiwan or something like that has like 20 million pounds that were already years old that are being sold as new stock.

Sent from my SM-G960U using Tapatalk

Click to expand...

Would "old" stock be an issue just for bending purposes? As I've got lots of old 6xxx and 7xxx material here for machining and never noticed any degradation due to age (well, just in me...).

Anyway, 5052 isn't an age-hardening material, so what could the issue be?

Ox said:

Just how much steel available today doo you think is virgin?

Alum would have a MUCH better likelyhood of being virgin that steel.
But that would likely be limited to material coming in from Russia and there abouts - via Iceland.


----------------------

Think Snow Eh!
Ox

Click to expand...

Service Center aluminum is recycled last I checked, but they are USA based. Who knows what they are recycling and how well they are analyzing the finished product.

Milland said:

Would "old" stock be an issue just for bending purposes? As I've got lots of old 6xxx and 7xxx material here for machining and never noticed any degradation due to age (well, just in me...).

Anyway, 5052 isn't an age-hardening material, so what could the issue be?

Click to expand...

Bending issue generally are only from wrong hardening temps and conditions. Like trying to bend t2 or t6 vs a good t3.

I was thinking maybe this is a reason why the OP was chewing threw cutters.

Sent from my SM-G960U using Tapatalk

Doug said:

BTW, Nucor reads this forum, back when I started noticing their crap I ranted about it on here. Got an email saying they'd like to call to discuss my issues with their products.

Click to expand...

Did they call? Did they say anything useful?

If they call again, ask them WTF?...

Doug said:

He said ranting about Nucor on a public forum was not the right thing to do.

Click to expand...

Well, sure. Not if you enjoy use of your limbs...

Well this is a real eye opener for me. My shop has just gotten a big enough order to justify getting all domestic material for a large order, for me $5-6k in 6061. Ended up with Kaiser, Hydro and Service. Could not for the life of me figure out why I was getting such different results. From birdsnesting to perfect 6's. Drove me insane.

Is it just a crap shoot then? Or is there a supplier that is consistantly better?

dangerboy said:

Well this is a real eye opener for me. My shop has just gotten a big enough order to justify getting all domestic material for a large order, for me $5-6k in 6061. Ended up with Kaiser, Hydro and Service. Could not for the life of me figure out why I was getting such different results. From birdsnesting to perfect 6's. Drove me insane.

Is it just a crap shoot then? Or is there a supplier that is consistantly better?

Click to expand...

Are you running milled parts, lathe parts or both? Crappy material is usually more forgiving milling it. I have never had any personal complaints about Hydro or Kaiser. Service Center is another issue, I have found their quality to be very inconsistent. All of Service Center is remelt so who knows what you get, even though they are considered USA domestic the origin of what they recycle could be anywhere. From what I read Kaiser will only recycle material from their own customers. I would just refuse Service Center and see if things get more consistent.

dangerboy said:

Well this is a real eye opener for me. My shop has just gotten a big enough order to justify getting all domestic material for a large order, for me $5-6k in 6061. Ended up with Kaiser, Hydro and Service. Could not for the life of me figure out why I was getting such different results. From birdsnesting to perfect 6's. Drove me insane.

Is it just a crap shoot then? Or is there a supplier that is consistantly better?

Click to expand...

If I am only machining, I like Kaiser, it is harder and makes better chips. If I am bending it Kaiser breaks and or cracks. Hydro and service center are softer and make stringy chips but I can bend it

Up until recently we purchased large amounts of Aluminum from Russia.
Price and availability were always good, the stuff machined great and was almost always dimensionally correct. Then out of the blue about 3 months ago we started to have problems fulfilling orders.
Now we are purchasing aluminum in the states and some out of Mexico.
Actually, the Russian aluminum machined better than some of what we have acquired here.
That said we are flat out done with Russia, and will never go back these SOB's should never have invaded Ukraine.