The article referenced by
@rust collector was more historical than technical.
I am going to claim that the basic reason the same plain carbon steels today, are stronger than period plain carbon steels, is 100% related to the amount of residuals and slag that early processes could not remove from the ladle. Also, state of art technology has significantly improved. This has affected everything. The Vacuum tube was basically a WW1 invention and was mature during WW2 and into the middle 1950's. Then the transistor was invented, then the microprocessor. Today's ability to quickly control, measure, process controls would be unbelievable by those steel makers who used to judge temperatures by eyeball.
I got to tell you, having lived through the semi conductor revolution, I never saw it. I took drafting class in college. I had my pencils, erasers, rulers, protractors, worked on a drafting board to produce dimensioned drawings of objects in three views. I am still amazed by dimensionally correct three dimension mechanical design software. I remember going through pages of paper drawings, manually adding dimensions to make sure the inside was not bigger than the outside. That took time, and, errors were found. What can be done with today's software is just amazing. Dick Tracy had a wrist watch with a video screen, and that was a cartoon. Now, we have cell phones. Never saw it coming.
From the data I have been able to find, early plain carbon steels had a lot of residual elements in them:
Residual Elements in Steel
https://www.totalmateria.com/page.aspx?ID=CheckArticle&site=kts&NM=205
Abstract:
Residual elements (Cu, Ni, As, Pb, Sn, Sb, Mo, Cr, etc.) are defined as elements which are not added on purpose to steel and which cannot be removed by simple metallurgical processes. The presence of residual elements in steel can have strong effects on mechanical properties. There is therefore clearly the need to identify and to quantify the effects of residual elements in order to keep these effects within acceptable limits.
Since so much scrap is recycled in the making of steel, “tramp elements” are a major concern.
https://www.tms.org/pubs/journals/jom/0110/manning-0110.html
One alternative to removing metallic tramp elements is to reduce their deleterious effects on steel properties. Most metallic residuals reduce steel hot strength and hot and cold ductility by segregating to and weakening grain boundaries. Tolerance to such chemical impurities could be improved through the design of alloys in which these elements were tied up in heterogeneously nucleating second-phase particles, which might not have the same negative effect on steel properties. Also, new near net shape casting processes, which will be described in following sections, may dramatically reduce the overall effect of residual elements for two reasons. As its name implies, near net shape casting describes solidification processes by which steel is cast in dimensions near to the specifications of the final product.
Might also look at the problem of micro inclusions and how they weaken steels.
Designers today, use data supplied by steel manufacturers, who test and provide the mechanical properties of their steels. Some questions I have, and would like to know, just what standards were being used in the 1890’s and when did the definitions of yield, ultimate baselined? Today, we are aware of the effect of low temperature on steel properties. From my reading, fatigue lifetime was unknown around World War 1, and so was knowledge about low temperatures and brittleness. I read that the first phase diagrams were came out in the 1890’s. And, in that time period, what mechanical properties were steel manufacturer’s reporting? I would like to know that, I do have a first edition of Machinery’s Handbook, (1916) I can tell you, there are serious gaps in the metallurgical knowledge of the period. The section on the heat treatment of carbon and alloys goes from Heat treatment A to heat treatment U. Actually not bad advice for the simple steels of the era. There is no reference to a steel specification such as SAEXXXX. Those standards came later. Specific “high speed tool” steels are referred to by maker, such as Burgess, Rex High Speed, Bethlehem self hardening. No compositional or material data is given on those high speed steels, just heat treatment suggestions. Anyone who spends any time looking at 19th century metallurgy, and knows what is available today, will see large gaps in period knowledge and technology.
Bessemer created a blast furnace technology that vastly increased the rate of steel production over any previous process, but he used Swedish iron. Swedish iron, by an accident of geology, is low in phosphors. Apparently Bessemer did not know that, but his licensee’s were using cheaper iron ores which were high in phosphorus and their steels were brittle. And they were suing. Bessemer found a chemist who created spiegeleisen
https://en.wikipedia.org/wiki/Spiegeleisen which removed the phosphorus. But you know, the Bessemer process, and all those early processes, could not remove non oxidizing elements. Most of the elements you listed are non oxidizing elements. And the question I have, because I don’t know this, is how are non oxidizing elements removed from the steels of today. One 1980’s SAE report I read, the increasing lifetime of wheel bearings was discussed. And the report directly related the increased fatigue lifetime to reduced micro inclusions from the decade before. Anyone claiming that steel from 1900 is as good as steel today is a dreamer.
An interesting data point, in Rifle Magazine did a review of the first Ruger M77’s in their Jan-Feb 1969 issue. In that article there is this quote:
Ruger technicians claim that during strength tests, a static load of at least 40,000 pounds was required to damage the locking lugs (there are two), and that, even then, the lugs did not shear away. Similar tests with Springfield and Mauser type mechanisms are said to show that the locking lugs of these action shear completely under loads 19,000 to 29,000 pounds.
The author of course is writing an informercial on Ruger M77 rifles, and educating you on what you need to know to buy Ruger rifles. The article is not about Mauser rifles or Springfield rifles, the article is selling Rugers, so we get this “taste” of data, but hey, it is data. The Springfield and Mauser bolts were certainly strong enough for the loads of the period, but the low yield at shear, compared to the 4140 steels used in the Ruger M77, show the much greater safety factor of later steels, and, a promise of a much higher fatigue life. Also, an examination of low temperature Charpy Impact tests show that good low carbon steels break at orders of magnitude less energy than alloy steels, such as 4140. There are good reasons why no one uses those primitive steels in safety critical applications such as receivers or rifle locking mechanism.
There is some data out there on WW1 era Mauser actions.
http://forums.accuratereloading.com/eve/forums/a/tpc/f/9411043/m/4281076061?r=8481020161
Okay, here we go again. Sorry, I'm paraphrasing Duane Wiebe.
The 1996 "core" assay of a generic WW-I era 1898 Mauser receiver:
Carbon: 0.29%
Sulfur: 0.022%
Phosphorus: 0.019%
Manganese: 0.45%
Silicon: 0.16%
Nickel: 0.05%
Chromium 0.02%
Molybdenum: <0.01% (trace)
Vanadium <0.01% (trace)
Copper 0.17%
Columbium: <0.01% (trace)
The 1996 "core" assay of a WW-I era 1898 Mauser bolt:
Carbon: 0.18%
Sulfur: 0.018%
Phosphorus: 0.014%
Manganese: 0.76%
Silicon: 0.23%
Nickel: 0.29%
Chromium: 0.06%
Molybdenum: <0.01% (trace)
Copper 0.15%
Aluminum: 0.02%
The following was the steel composition specified by the Mausers:
Carbon LT 0.40%
Manganese LT 0.90%
Copper LT 0.18%
Silicon LT 0.30%
Phosphorous LT 0.04%
Sulphur LT 0.06%
This is from page 103
Rifle & Carbine 98: M98 Firearms of the German Army from 1898 to 1918 Dieter Storz
The material looks to be a manganese steel alloy. The copper is most likely a containment, with a percentage to limit the amount, it could be that copper added for easy machining, either way, it detracts from the steel properties. Specified property requirements were: Ultimate 78.2 Ksi, Yield 36.9 KSI
, elongation 15%. A yield under 40 KSI probably means these are the desired properties of normalized steel.
Silicon, phosphorous and sulphur were actually undesirable, but unavoidable based on the ladle linings, so the percentages are limited. The load imparted to the lugs and the receiver seat is an impact load. Phosphorous has the ability to increase steel strength, hardness, and hardenability, but, sulphur and phosphorous adversely affect the material’s toughness, fatigue strength, which are critical properties in a rifle receiver. The other stuff, in the assay, is crap. To repeat, this stuff is crap that got into the steel. That nickel, chromium, molybdenum, vanadium, columbium, are all containments. Instead of making this some super duper advanced alloy steel, these “residuals” unpredictably detract from the properties of the steel.
These residuals are elements that the Bessemer and Open Hearth processes were not able to oxidize during the oxygen blow. They come from multiple sources, the most common one in today’s world, is scrap. Scrap is often contaminated with coatings of various kinds, and there is nothing to indicate that the steel manufactures were particular about the segregation of scrap. They might have been tossing everything and anything into the ladle. Waste in steel plant was collected and thrown back into the process, which also gave a slow but steady increase in the residual content, especially of copper and nickel, as these elements are not oxidized and removed in steel making.
Steels from the 1890’s and through the 1920’s are not of interest to the Archeological metallurgy community. They are much more interested in Medieval and earlier steel technologies, and there are books on steel composition and material properties on rare, existing specimens. I have one on Medieval sword compositions up to 1600. Really neat to read, but there is almost nothing on the period prior to, and after WW1. What material composition and property strength is in the public domain shows that early steels vary unpredictably in composition, and the material properties also vary. Pre vacuum tube technology has an inconsistency such that I came to the conclusion that it makes no sense to exceed period loads and pressures, or even, use the things at all in custom applications, where cheaper, modern alternatives are available.
This is from a paper by Bain, in the 1920’s. This paper was referenced in a post WW2 metallurgical book, and the author was making the case that plain carbon steels, which were the type of steels used in Krag’s, Mausers, M1903’s, heat treat erratically. Post WW2 (I don’t have the WW2 version) these plain carbon steels are being called shallow hardening. The graph to the right shows hardness by depth with these plain carbon steels. And, the hardness depth is varying, and not consistent through the coupon.
Bain, and this is the Bain of whom Bainite is named, took identical sections of plain carbon steels, placed a selection in a heat treat oven, and acid etched the finished products. Bain showed that given identical plain carbon steel, in the same heat treat oven, specimens varied in heat treatment depth. The dark parts show the amount of steel that did not harden. This variability was more or less eliminated by alloy steels, which hardens deeply and consistently. This is a real concern as unless the part is completed hardened, it won’t hold a load as designed.
So, given the unpredictable and varying composition of these early steels, and then the tendency of the steel to harden erratically, these early steels are inferior in all respects to the same steels today.
I have gone through modern metallurgy books, and this cautionary tale told to the WW2 generation is missing. Science advances one funeral at a time and I think those who were pathologically attached to plain carbon steels, and shunned alloy steels, are gone. So a section on the advantages and superiority of alloy steels over plain carbon steels is no longer needed. But there was a time when the case had to be made.
I remember the period when calcified engineers were called “slide rule” engineers.
I can still use the C/D scales on my slide rule,
And I still occasionally use this old adding machine to balance my checkbook
However, I have gotten so stupid that I find it easier to use web calculators for tasks that I used to do on paper.
Just as no one today would think of using a slide rule at college, or at work, no living engineer in sound mind and body would use those low grade steels used in those vintage rifles and pistols, in safety critical applications. Incidentally, I recently purchased a $60.00 transmission flywheel. Talked to the manufacturer and they use 4340 steel. I would have liked to talked to a metallurgist and asked his opinion about using 1035 steel as a flywheel material.
I cannot quantify the how steel has improved over time, I do not have samples of steel and measurements of their material properties and elements. However, things have improved. Who today would be writing love letters to Rambler because their car lasted 100,000 miles?
There is a lot more to the improvement of automotive engine lifetime than just steel improvements. Those old single stage machines could not hold the tolerances of modern equipment, and the multi functionality of CNC machines allows multistage operations at one machining center, and computer measurement of the previous part. A bud of mine went to the subcontractor making Les Baer 1911 frames. On table 1, frame rails were being cut, on table 2, a computer probe was real time measuring the previous frame cut, and feeding back the tool wear to the cutting arm on table 1. Parts across hundreds, if not thousands of the same model, are for all intents and purposes, dimension ally identical. Parts do not sit in bins for days or weeks, like they were in vintage factories. Errors are discovered quickly, processes are set up so there is as little of in process inventory as possible.
I feel comfortable with post WW2 steels, but this is only a feeling. I do not have the time phased compositions or material properties to prove anything. And bad things still happen, such as the Japanese steel maker Kobe shipping non conforming steels, and committing fraud for decades
Kobe Steel scandal: how did it happen?
https://www.bbc.com/news/business-43298649
I can say, based on my experience of a case head failure in my RIA 1911, today's pistols are strong.
rounds were hitting the feed ramp. The magazine release held the magazines too low and bullets were nose diving, and getting stuffed in the case. I am confident that is why the case head blew. The base of the magazine was blown out, my beautiful Herret cocobolo grips cracked. And I was hit by something that caused a bruise on my chin. I was wearing shooting glasses. All I had to do was field strip, wipe out the powder residue, re oil, insert a new magazine, and I continued shooting. I am of the opinion that such an over pressure event would have ruined a WW1 1911. I am still shooting my RIA, but I purchased a higher magazine release. So far, so good.
I am aware of a shooter who must have had a squib in his Colt 1911. A bud of mine investigated the strange kaboom which happened to an older man at the range. It must have been a squib that blew the case head. The next bullet knocked the bullet out of the barrel, but bulged the barrel and slide, and that pistol was ruined. Opps! Try hard enough, and anything made by man, can be unmade by man.
