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Tool steels
Int. ]'. Maeh. Toc,l Des. Res. Vol. 3 ,p. 227. Pergamon Press 1964. Printedin Great Britain
BOOK REVIEW Tool Steels; ROBERTS, HAMAKERand JOHNSON (3rd Edition). American Society for Metals 780 pp. 1962. 100s. TOOL STEELSinclude some of the most complex of alloys and their range is probably the most extensive of any that can reasonably be grouped under a single functional title. Whilst a good deal can be done to rationalize the subject in terms of established metallurgical principles of which the use of phase diagrams and transformation plots and the association of certain properties with specific microstructures may be cited as examples, the ultimate goal of designing a tool steel in terms of composition and treatment for any particular application is barely in sight. Of the many obstacles to this, not the least is that of elucidating, in fundamental terms, the properties required in tool material. We can recognize the cruder requirements of course: cold-work die steels must be tough, high-speed cutting tools must retain their hardness at high temperature and hot-working applications require a resistance to craze-cracking. Thus there is no difficulty in classifying tool steels into broad types and associating each with a fairly distinctive metallurgical background. But it is the subtleties that count, the very sensitive dependence of cutting performance on composition and heat lreatment for example, and it is here that both metallurgical and engineering science fails us. The inevitable consequence is a proliferation of materials each with its uses, its vices and its uncertainties. The status of tool-steel design is not unlike that of modern drugs in this respect. It is against this background that a book on the subject must be judged. The publishers describe this edition as "the world's most comprehensive and authoritative publication on tool steels . . . based on scientific findi~ gs and engineering facts". This is true. If the scientific findings are not all that fundamental, the engineering facts are profuse and of narrow application, and these two aspects but tenuously connected, it is the fault of the subject and not of the book. The emphasis of the book is on selection and this is surely the most useful approach. The various chapters contribute to this central theme--a brief review of tool-steel making, a thorough discussion of testing methods and heat treatment and a concise account of the physical metallurgy of alloy steels. Then follows a chapter on classification which leads into the second half of the book dealing with carbon, low-alloy, special-purpose, cold-work, hot-work and high-speed steels, each constituting a chapter. The index is adequate and the whole style of the book is conducive to easy reference. The exclusive use of American specifications detracts from its "handbook" value to English users but the main virtue of the book in providing a detailed background is unimpaired by this. The book, like its earlier editions, should find favour amongst a wide field of tool users, treaters, investigators and designers. S. G. GLOVER
The University, Birmbsgham, 15.
227
BOOK REVIEW Tool Steels; ROBERTS, HAMAKERand JOHNSON (3rd Edition). American Society for Metals 780 pp. 1962. 100s. TOOL STEELSinclude some of the most complex of alloys and their range is probably the most extensive of any that can reasonably be grouped under a single functional title. Whilst a good deal can be done to rationalize the subject in terms of established metallurgical principles of which the use of phase diagrams and transformation plots and the association of certain properties with specific microstructures may be cited as examples, the ultimate goal of designing a tool steel in terms of composition and treatment for any particular application is barely in sight. Of the many obstacles to this, not the least is that of elucidating, in fundamental terms, the properties required in tool material. We can recognize the cruder requirements of course: cold-work die steels must be tough, high-speed cutting tools must retain their hardness at high temperature and hot-working applications require a resistance to craze-cracking. Thus there is no difficulty in classifying tool steels into broad types and associating each with a fairly distinctive metallurgical background. But it is the subtleties that count, the very sensitive dependence of cutting performance on composition and heat lreatment for example, and it is here that both metallurgical and engineering science fails us. The inevitable consequence is a proliferation of materials each with its uses, its vices and its uncertainties. The status of tool-steel design is not unlike that of modern drugs in this respect. It is against this background that a book on the subject must be judged. The publishers describe this edition as "the world's most comprehensive and authoritative publication on tool steels . . . based on scientific findi~ gs and engineering facts". This is true. If the scientific findings are not all that fundamental, the engineering facts are profuse and of narrow application, and these two aspects but tenuously connected, it is the fault of the subject and not of the book. The emphasis of the book is on selection and this is surely the most useful approach. The various chapters contribute to this central theme--a brief review of tool-steel making, a thorough discussion of testing methods and heat treatment and a concise account of the physical metallurgy of alloy steels. Then follows a chapter on classification which leads into the second half of the book dealing with carbon, low-alloy, special-purpose, cold-work, hot-work and high-speed steels, each constituting a chapter. The index is adequate and the whole style of the book is conducive to easy reference. The exclusive use of American specifications detracts from its "handbook" value to English users but the main virtue of the book in providing a detailed background is unimpaired by this. The book, like its earlier editions, should find favour amongst a wide field of tool users, treaters, investigators and designers. S. G. GLOVER
The University, Birmbsgham, 15.
227