Scrap metal for reuse has a value directly related to its ease of being remelted, refined, and then turned into new material versus the cost of just smelting new ore. That much should be self-evident. Aluminum is a very recyclable material. Unlike new ore, remelt aluminum from scrap takes only about 25% the energy of ore to refine into new metal. This is because ore is found in the form of Alumina (AlO) having a melting point of about 1900C versus 500 C for aluminum metal. This also means that most of the alloying agents in aluminum are also easily removed as they generally have much higher melting points than aluminum itself. Iron on the other hand takes about the same energy to refine whether it is new ore or scrap. Scrap iron is only attractive where ore is not readily available or can cheaply be shipped to a smelter. This is why Japan preferentially buys scrap iron and steel. But, the value per pound is low due to the ready availability of ore in many locations and that smelters are generally co-located with the ore. Here shipping scrap costs more than simply digging up new ore. Brass, Bronze, and copper are all relatively rare alloys. Copper is not always readily available. Again, remelt is done at fairly low temperatures so it is easily accomplished. Much copper is only found today in the form of oxides and sulfides in lower grade ores. These require sophisticated chemical processing or considerably more energy than scrap to turn into new alloys.
Coming late to this thread, but with an interesting anecdote... SOME of the aluminium was used by war industries...BSA and other motorcycle manufacturers got issued it! Brian Crichton, an ex-BSA staffer, used to write for the classic motorcycle press. They had a LOT of trouble heat-treating aluminium they were issued, and he was sent to the Middle East at one point mid-war after a series of seizures on BSA M20 despatchers' bikes. It turned out that oversize pistons in boxes...for fitting after rebores...were "growing" out-of-round - just sitting in their boxes on the shelf in the desert heat!!! Obviously Middle Eastern Command was going through a LOT of rebores, given the minimal filtering on bikes and the sandy environment! The pistons were fitted straight from the box, and nipped up in use soon after. When Crichton returned from the Middle East and tracked the specific batches of metal back up the supply chain - the metal used for the batches he'd identified had come from the scrap metal drive!
Outside of the UK, but while browsing this pleasing blog I pottered onto these rather nice shots of some US scrap-driving:
Didn't Churchill once say that the biggest value of anti aircraft fire during the Battle of Britian was to let people hear that they were fighting back? I can't find the source of that one at the moment.
Yep - on their way home after VJ Day, the Royal Australian Navy simply pushed dozens of carried aircraft off the fantails of their carriers as they entered Sydney Harbour roads Some of them with zero combat miles, just ferry miles on them!
Good background rhythm Some of us remember the rag-and -bone-man: "Any old Bo...nes". https://en.wikipedia.org/wiki/Rag-and-bone_man As a child I imagined them collecting dead bodies. They collected metal too - perhaps contributed to the war effort in a smallway.
The Scotsman 30 January 1940 The Sphere 07 September 1940 Illustrated London News 11 October 1941 Newcastle Journal 1 December 1942 Newcastle Journal 12 October 1944
I would agree with this.I remember an article claiming the effort was more involved in morale boosting of the civilian population than everything else....there were also propaganda posters urging housewives to donate aluminium saucepans for the war effort with the message given as to turn the aluminium into Spitfires. Regarding the burning off of iron railings,usually found around grand Victorian buildings,the work left small stumps protruding from the railing concrete plinths...a danger to those who might fall on to them.As I remember these railings were not recovered after the war and the plinths were still in a bad state 10 years after the war ended. Scrap metal has its value especially such as copper.While in Normandy,I noted a plinth on the high ground above Arromanches which may have held a radar device or something similar.The earthing bar or strap was still intact and was mlld steel which would normally be copper....the Germans were obviously short of copper and made do with mild steel. The German copper shortage was reflected by Vichy legislation in the unoccupied zone where Petain laid down that each family should provide to the authorities a couple of kilos of copper per month which meant that families had to give up anything made of copper or scavenge the countryside for copper.
Removing all the cast iron railings was the sort of gesture that gave people the impression that they were doing something - like interning all foreigners. The official history on British War Production does show that supplies of scrap metal for steel making rose buy about 20% a year between 1938 and 1939-41 (pp155-156) and by 50% in 1943 HyperWar: British War Production [Chapter IV] and HyperWar: British War Production [Chapter V]
The usefulness of scrap metal depends upon the nature of that metal so for example much armour plate can only be economically recycled to produce more armour plate of the same specification. Some iron is worth recycling some is not. Most cast iron railings contain too much carbon and/or sulphur, whilst this can be removed it is not worth the cost if good ore is available for smelting. Almost all iron can be used to make steel but not all iron is worth the effort economically. Similarly not all iron ore is the same - that available for mining in Britain had a lower ferrous content than that from Norway and therefore more had to be smelted for the same quantity of steel production. This meant that more tons of coke had to be used for a given quantity of steel. The loss of Norway and its ore created something of a panic in the Ministry of Supply. Unfortunately it was not until Churchill's reorganisation that an effective Department of Materials was created and the resultant scrap drive was directed by Civil Servants without the necessary technical expertise. Much scrap could not be used, however the Official History shows that a significant amount was used for steel production. 1940 6,527,000 tons 1941 6,622,000 tons The idea that the whole scrap drive was pretext to raise public morale is therefore spurious. The secret dumping of unusable scrap was most likely a means of concealing civil service incompetence
Really interesting, Robert. Had only ever heard a certain cynicism from people that have a modern interest in metals' re-usability. Can I ask which Official History you're referring to? Ministry of Supply?
British War Production. Chap IV. Sale Grammar School was one of only three Grammar Techs created under the 1944 education reforms (the Attlee admin didn't like the idea) and were the brainchild of C P Snow who wanted to turn out literately educated scientists, technologists and engineers. I was in the technical stream and so got taught how to build and run a blast furnace etc as well as the metaphysical poets and Louis XIV's foreign policy. This included being able to operate a screw cutting lathe and black smithing ( I was rather good at the latter). So I learnt about foundry work. Looking back this has been more use than my 1st degree (economics)
Railings, Clissold Park ,London You can see where the old railings were lopped off and after the war new ones inserted. So What Really Happened to our Railings? So What Really Happened to our Railings?
