A study of the interactive effects of strain, strain rate and temperature in severe plastic deformation of copper

Abstract The deformation field in machining was controlled to access a range of deformation parameters—strains of 1–15, strain rates of 10–100,000 s −1 and temperatures of up to 0.4 T m —in the severe plastic deformation (SPD) of copper. This range is far wider than has been accessed to date in conventional SPD methods, enabling a study of the interactive effects of the parameters on microstructure and strength properties. Nano-twinning was demonstrated at strain rates as small as 1000 s −1 at −196 °C and at strain rates of ⩾10,000 s −1 even when the deformation temperature was well above room temperature. Bi-modal grain structures were produced in a single stage of deformation through in situ partial dynamic recrystallization. The SPD conditions for engineering specific microstructures by deformation rate control are presented in the form of maps, both in deformation parameter space and in terms of the Zener–Hollomon parameter.

[1]  W. F. Hastings,et al.  Predicting the strain rate in the zone of intense shear in which the chip is formed in machining from the dynamic flow stress properties of the work material and the cutting conditions , 1977, Proceedings of the Royal Society of London. A. Mathematical and Physical Sciences.

[2]  W. Dale Compton,et al.  Low-cost manufacturing process for nanostructured metals and alloys , 2002 .

[3]  K. Lu,et al.  Effect of the Zener-Hollomon parameter on the microstructures and mechanical properties of Cu subjected to plastic deformation , 2009 .

[4]  Fenghua Zhou,et al.  High tensile ductility in a nanostructured metal , 2002, Nature.

[5]  W. D. Compton,et al.  Bulk nanostructured materials by large strain extrusion machining , 2007 .

[6]  N. Hansen,et al.  High angle boundaries formed by grain subdivision mechanisms , 1997 .

[7]  Y. Estrin,et al.  Dislocation structure and crystallite size in severely deformed copper by X-ray peak profile analysis , 2005 .

[8]  Srinivasan Chandrasekar,et al.  Severe plastic deformation of copper by machining: Microstructure refinement and nanostructure evolution with strain , 2007 .

[9]  S. Chandrasekar,et al.  Stabilizing nanostructured materials by coherent nanotwins and their grain boundary triple junction drag , 2009 .

[10]  Lei Lu,et al.  Ultrahigh Strength and High Electrical Conductivity in Copper , 2004, Science.

[11]  E. G. Thomsen,et al.  Mechanics of plastic deformation in metal processing , 1965 .

[12]  G. Thomas,et al.  Substructures in explosively deformed Cu and Cu-Al alloys , 1964 .

[13]  M. C. Shaw Metal Cutting Principles , 1960 .

[14]  G. Boothroyd Temperatures in Orthogonal Metal Cutting , 1963 .

[15]  Seongeyl Lee,et al.  Severe Plastic Deformation by Machining Characterized by Finite Element Simulation , 2007 .

[16]  J. Steeds Dislocation arrangement in copper single crystals as a function of strain , 1966, Proceedings of the Royal Society of London. Series A. Mathematical and Physical Sciences.

[17]  M. Meyers,et al.  Microstructural evolution in copper subjected to severe plastic deformation: Experiments and analysis , 2007 .

[18]  E. Pereloma,et al.  Microstructures and properties of copper processed by equal channel angular extrusion for 1–16 passes , 2004 .

[19]  Jihong Hwang,et al.  Large strain deformation field in machining , 2006 .

[20]  J. Embury,et al.  The structure and properties of drawn pearlite , 1966 .

[21]  Yinmin M Wang,et al.  Three strategies to achieve uniform tensile deformation in a nanostructured metal , 2004 .

[22]  Jihong Hwang,et al.  Large strain deformation and ultra-fine grained materials by machining , 2005 .

[23]  W. Dale Compton,et al.  Severe plastic deformation (SPD) of titanium at near-ambient temperature , 2006 .

[24]  R. Valiev,et al.  Principles of equal-channel angular pressing as a processing tool for grain refinement , 2006 .

[25]  S. G. Srinivasan,et al.  Deformation twinning in nanocrystalline copper at room temperature and low strain rate , 2004 .

[26]  F. J. Humphreys,et al.  Recrystallization and Related Annealing Phenomena , 1995 .

[27]  L. Samuels,et al.  Metallographic polishing by mechanical methods , 1982 .

[28]  K. Lu,et al.  High density nano-scale twins in Cu induced by dynamic plastic deformation , 2005 .