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Ann. Rev. Mater. Sci.

1984. 14 :,231-78

ANNUAL REVIEWS

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HIGH-SPEED MACHINING OF METALSl
D. G. Flam, R. Kamanduri, and M. Lee
Annu. Rev. Mater. Sci. 1984.14:231-278. Downloaded from www.annualreviews.org by Universidad de la Frontera on 09/01/10. For personal use only.

General Electric Company, Corporate Research and Development,Schenectady, New York 1 2301
INTRODUCTION

The most obvious rationale for pursuing a study of high-speed machining (HSM) is the promise of increased metal removal rate (MRR), which is the product of surface speed, depth of cut, and feed rate. While HSM generally means high surface speed, most practical applications also require some minimum chipload and this means a feed rate above a minimum value. Otherpotential benefits of HSM include improved surface finish and reduced cutting forces. The term high-speed machining is a relative one from a materials view­ point because of the vastly different speeds at which different materials can be machined with acceptable tool life. For example, it is easier to machine aluminum at 1 ,800 surface meters per minute (smm) [6,000 surface feet per minute (sfpm)]than titanium at 1 80 smm (600 sfpm). One way of defining HSM is to consider it as that speed beyond which chip morphology is markedly different from the conventional continuous chip. While attractive from a concise technical standpoint, this is not very useful as a practical definition. For this reason, it is generally preferable to define machining speeds quantitatively in terms of specificranges. A suggestion by Prof. B. F. von Turkovich is that 600-1 ,800 smm (2,000-6,000 sfpm) should be termed high-speed machining, 1 ,800-1 8,000 smm (6,000-60,000 sfpm) very high­ speed maching (VHSM), and greater than 1 8,000 smm (60,000 sfpm) ultrahigh-speed machining (U HSM) (1). An alternative definition scheme is to refer to speeds up to 1 5,000 smm (50,000 sfpm) as HSM and speeds above that asUHSM, only because the former can be thought of as achievable with conventional-type machine tools whereas the latter might require ballistic-type equipment. In the case of very difficult-to-machine alloys, it is
1 The US Government has the right to retain a nonexclusive royalty-free license in and to any copyright covering this paper.

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FLOM, KOMANDURI & LEE

preferable to usethe term high-throughput machining (HTM) rather than high-speed machining in order to keep a proper focus on realistic goals in machining.
EARLY WORK

Numerous high-speed machining studies have been reported in the literature covering a variety of work materials including steels, cast iron, lead, brass, aluminum, stainless steel, titanium, lead-antimony alloys, and copper. The tool materialshave included carbon steels, high-speed tool steels, carbides, and oxides. The speeds used have ranged up to 7,600 smm (25,000 sfpm) using modified conventional machine tools and up to 73,000 smm (240,000 sfpm) using ballistic apparatus. It is not clear from the reported results [with the possible exception of Siekmann's work (2)] whether or not horsepower requirements were adequate, machine toolswere stiff enough, or data collected were adequate to warrant some of the broad conclusions reached. Since the interpretation and analysis of the data were dependent on the precision and frequency response of the instrumen­ tation available at the time, it was only natural that some conflicting claims should arise. Most of the early investigators were oriented toward mechanical engineering andtherefore the metallurgical aspects of high­ speed machining did not receive the same degree of attention. The origin of much of the earlier interest in high-speed machining was the controversial work reported by Salomon (3) in high-speed cutting of copper, bronze, and aluminum at speeds up to 1 ,500 smm (5,000 sfpm). Based on these studies, he filed the first known patent application in high­...
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