DOUBLE STRENGTH IRON DEVELOPED

Rotorua Morning Post, Issue 5309, 23 January 1947, Page 3

DOUBLE STRENGTH IRON DEVELOPED

YIRTUALiLY NEW INDUSTRIAL MATERIAL. LONDON. A major discovery in industrial science was announce* recently at the 25th axmiversary of the British Cast Iron Research Association (saj-s the scientific correspondent of the Manchester Guardian). As the result of extensive researches in the association's laboratories, cast iron of douible the crdinary strength can now be made by a simple and generaliy new. process. Dr. Harold Hartley, the president of the association, descrihecl it as the biggest sing-le 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 Researeh, has laboratories at Bordesley Hall, Alvechurch, near Birmingham. Oue of the Iines of researeh which it has pursued for many years is the invejjtigaltjon of how molten iron crystallises, in order to discover the reasons why cast iron posesses its chai-acteristic properties. Parallel with these researches systematic studies have been followed on the effects of small quantities of other ingredients on the qualit'ies of the cast iror.. The aim has been to find or.t why tliings happen as they do, and not to solve any particular industrial problems. Varied Compouiuls. In 193G the association published results which showed that the addition of titanium compounds eould give the graphite in cast iron a fmo structure. Now the strength of cast iron depends, among other factors, on the form of thc graphite it contains. Arising oet of their titanium work, the scientists of the association have sueceeded iii casting* iron which contains graphite in a nodular or spherical forpi and not in the siringy, elongated flakes usually fcund 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 passible to make strong cast iron with special •eompositions and complicated treatmenls which were relatively expensive aua diffieult. The new process is particularly applicab'le 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 i valuable as a base from which special cast irons can be made. The details of Ihe process have not yet been published, as a nunvber of provisional patents have been filed. ! At least 12 new lines of development j researeh are required to discover the ! liest ways in which industry can use the new cast iron. It is, in fact, virtually a new industrial mateiial.