Buzzkill Posted January 13, 2020 Share Posted January 13, 2020 Whether it's alloy content that changes, crystal structure, or something else, many of us have personally experienced significantly different behaviors/results within inches of the same bar of stock. When that happens it doesn't really matter if someone claims it doesn't happen, can't happen, or won't happen. It just is. I have personally had rebar stock that behaved like mild steel on one section of the bar and didn't harden when quenched and then a foot away or so on the same bar of stock it did harden and break. I've also had A36 where I've drilled several holes without incident and then the next one didn't get more than about 1/8" in before the bit started screeching. Skipping that hole temporarily and moving over to the next resulted in another hole that drilled as expected. This was on stock that I had not heated at all before drilling, so it was not affected by forging or anything of that nature. Whenever that happens to me I find that heating the piece up to a dull red and letting it cool to ambient temperature tends to allow for normal drilling. So again, regardless of what anyone claims is true or not true, it's pretty darned hard to convince some of us who have personally experienced differences in the same piece of stock within a few inches that it's all homogeneous tightly regulated product. Quote Link to post Share on other sites
jlpservicesinc Posted August 29, 2020 Share Posted August 29, 2020 Well said Buzzkill. Observations are often times in practical moment real use, vs what happens based on specs which get touted as the only "Real" information. Quote Link to post Share on other sites
Chris Williams Posted August 29, 2020 Share Posted August 29, 2020 On 1/13/2020 at 5:51 PM, Buzzkill said: ...pretty darned hard to convince some of us who have personally experienced differences in the same piece of stock within a few inches that it's all homogeneous tightly regulated product. Specs tend to control bulk properties and define allowable types, sizes, and spacing for defects. The drilling issue in A36 could easily be due to hitting an inclusion. This does not apply to all anecdotes presented, but several are within the allowable variation in the material. Plus, for those that only control a limited number of properties (typically tensile strength) to a minimum and with no control over heat treat response (because the product is intended to be used as delivered or isn't meant to be hardened), it should not be surprising that the material is inconsistent in other ways that are not controlled by the spec. The behavior of the material once it has been further thermally processed (by us) is out of scope of the spec entirely. Quote Link to post Share on other sites
localsmith Posted September 30, 2020 Share Posted September 30, 2020 Interesting discussion. I've never personally noticed a difference between 1018 (new steel?) and A36. I definitely can see how it can have inclusions but during the forging process those should be forged out (or rather melted out) if they are made out of aluminum and any other alloys that have a lower melting point than steel unless I'm mistaken. Quote Link to post Share on other sites
Steve Sells Posted September 30, 2020 Share Posted September 30, 2020 Funny you say that; when you stated in another thread how you cant forge weld A36 but can 1018. as well as how its harder to forge, and what is this about Aluminum? any in the melt as a contaminate or deoxidant would float out in the slag Quote Link to post Share on other sites
ThomasPowers Posted September 30, 2020 Share Posted September 30, 2020 Al was used to "kill" steel. "Killed steel is steel that has been completely deoxidized by the addition of an agent before casting such that there is practically no evolution of gas during solidification." wiki Quote Link to post Share on other sites
DHarris Posted October 3, 2020 Share Posted October 3, 2020 On 4/23/2019 at 11:23 PM, ThomasPowers said: We have sand dunes out here and you could select finer sand wind or water sorted. What about diatomaceous earth? Quote Link to post Share on other sites
Frosty Posted October 3, 2020 Share Posted October 3, 2020 Microscopic, Silicate, Diatom skeletons and relatively pure. It should work better than sand. I like looking at them under a microscope, they're as varied as snowflakes. Frosty The Lucky. Quote Link to post Share on other sites
SLAG Posted October 3, 2020 Share Posted October 3, 2020 Folks, Silica sand works a treat for me. It is relatively cheap. You can get it a building supply store. The stores that carry block, bricks, etc. SLAG. Quote Link to post Share on other sites
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