DOUBLE STRENGTH IRON

Bay of Plenty Beacon, Volume 10, Issue 87, 27 January 1947, Page 3

DOUBLE STRENGTH IRON

VIRTUALLY NEW INDUSTRIAL MATERIAL

A major discovery in industrial science was announced recently at the 25th anniversary of the British Cast Iron Research Association (says the scientific correspondent of the Manchester Guardian). As the result of extensive researches in the association’s laboratories, cast iron of double the ordinary strength can now be made by a simple and generally new process. Dr. Harold Hartley, the president of the association, described it as the biggest single advance in the metallurgy of cast iron in the 20th century. The association, which is financed jointly by the industry and by the Department of Scientific and Industrial Research, has laboratories at Bordesley Hall, Alvechurch, near Birmingham. One of the lines of research which it has pursued for many years is the investigation of how molten iron crystallises, in order to discover the reasons why cast iron possesses its characteristic properties. Parallel with these researches systematic studies have been followed on the effects of small quantities of other ingredients on the qualities of the cast iron. The aim has been to find out why things happen as they do, and not to solve any particular industrial problems. Varied Compounds

In 1936 the association published results which showed that the addition of titanium compounds could give the graphite in cast iron a fine structure. Now the strength of cast iron depends, among other factors, on the form of the graphite it contains. Arising out of their titanium work, the scientists of the association have succeeded in cashing iron which contains graphite in a nodular or spherical form and not in the stringy, elongated flakes usually found in grey cast iron.

This new kind of cast iron has twice the tensile strength of ordinary cast iron, and is three times as resistant to shock. Hitherto it has been possible to make strong cast iron with special compositions and complicated treatments which were relatively expensive and diffcult. The new process is particularly applicable to the kinds of iron most easily cast and least subject to shrinkage on cooling and most easy to machine. It is thought that the new cast iron will be particularly valuable as a base from which special cast iron can be made.

The details of the process have not yet been published, as a number of provisional patents have been filed. At least 12 new lines of development research are required to discover the best ways in which industry can use the new cast iron. It is, in fact, virtually a new industrial material.