This is part of the collection of films made by Sheffield teacher William Gordon Gregory.  This is the second part of a film showing how specialised steel is making and the various tests that are made to determine the quantities of added substances. The film begins showing the ‘critical temperature’ as 900c.  Diagrams show the gamma pattern and the alpha pattern.  It then shows the quantities of the ingredients: iron 98.5 LB, carbon 13 oz..  A furnace is shown, and then the molecular...

This is part of the collection of films made by Sheffield teacher William Gordon Gregory.  This is the second part of a film showing how specialised steel is making and the various tests that are made to determine the quantities of added substances. The film begins showing the ‘critical temperature’ as 900c.  Diagrams show the gamma pattern and the alpha pattern.  It then shows the quantities of the ingredients: iron 98.5 LB, carbon 13 oz..  A furnace is shown, and then the molecular structure of the steel.  A graph shows the temperature of ingot ‘C’ as it cools down against time, with the critical temperature shown in two cases, beginning with austenite; showing the internal structure in diagrams, with the proportions of 86.5% iron and 13.5 carbon.  And then for pearlite, which includes 1/6 oz sulphur and 1/6 oz phosphorous.  Also shown is silicon 5 oz, vanadium 1 ½ oz and manganese 4 oz.  These are shown being mixed together before it shows examples of calcium and nickel, chromium and iron, and magnesium, which is put into a jar of oxygen.  Then we see samples of calcium mixed with iron and carbonized with iron. Various of these materials are shown as they are placed into a tube of oxygen, showing the resulting compounds.  Other ingredients shown are vinegar and ammonia.  A large metal container is shown being lined with fire bricks, whilst materials are mixed together.  A container of old nuts and bolts is emptied onto the floor and shovelled into the furnace.  This is followed by adding steel ingots and other pieces of scrap metal.  A spark lights the (electric) furnace.  The steel workers stop and have a tea break before continuing shovelling in scrap metal.  Small stones are then shovelled in followed by larger stones.  This is all mixed in the furnace and the film comes to an end.