The Effect of Workpiece Hardness and Cutting Speed on the Machinability of AISI H13 Hot Work Die Steel When Using PCBN Tooling
Author:
Ng Eu-Gene1, Aspinwall David K.2
Affiliation:
1. University of Birmingham, School of Manufacturing and Mechanical Engineering, Edgbaston, Birmingham, B15 2TT, UK 2. University of Birmingham, School of Manufacturing and Mechanical Engineering, IRC in Materials for High Performance Applications, Edgbaston, Birmingham, B15 2TT, UK
Abstract
When machining hardened steel (⩾45 HRC) with polycrystalline cubic boron nitride (PCBN) tooling, the cutting speeds used produce high temperatures in the primary shear zone, which are sufficient to plasticize the workpiece. The paper initially reviews the effect of workpiece hardness and cutting speed on chip formation, workpiece surface integrity and cutting forces. Equations are detailed for determining the primary shear zone temperature, the proportion of heat conducted into the workpiece and the shear flow stress. Following on from this, experimental work is presented involving the orthogonal machining of AISI H13 hot work die steel with PCBN tooling. Tests were carried out over a range of cutting speeds with workpieces of different hardness, in order to provide cutting force, shear angle, chip morphology and primary shear zone thickness data. The shear flow stress decreased with increasing cutting speed and/or workpiece hardness. With the AISI H13 heat treated to 49±1 HRC, the stress magnitude changed more significantly with cutting speed and the proportion of heat conducted away from the workpiece approached 99 percent at 200 m/min. Shear localized chips were produced with white unetched layers due to intense heat generation followed by rapid cooling.
Publisher
ASME International
Subject
Industrial and Manufacturing Engineering,Computer Science Applications,Mechanical Engineering,Control and Systems Engineering
Reference28 articles.
1. Komanduri, R., Schroeder, T., Hazra, J., Von Turkovich, B. F., and Flom, D. G., 1982, “On The Catastrophic Shear Instability In High Speed Machining Of An AISI 4340 Steel,” ASME J. Ind., 104, pp. 121–131. 2. Shaw, M. C., 1997, Metal Cutting Principles, Oxford Science Publications, ISBN 0-19-859020-2. 3. Wu, D. W., and Matsumoto, Y., 1990, “The Effect Of Hardness On Residual Stresses In Orthogonal Machining Of AISI 4340 Steel,” ASME J. Ind., 112, pp. 245–252. 4. Matsumoto, Y., Barash, M. M., and Liu, C. R., 1986, “Effect Of Hardness On The Surface Integrity Of AISI 4340 Steel,” ASME J. Ind., 108, pp. 169–175. 5. Moufki, A., Molinari, A., and Dudzinski, D., 1997, “Modelling Of Orthogonal Cutting,” First French And German Conference On High Speed Machining, University of Metz.
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