Faculty Profile

Pascal Bellon

Materials Science and Engineering
Pascal Bellon
Pascal Bellon
Hamer Professor
312D Materials Science & Eng Bld
1304 W. Green
Urbana Illinois 61801
(217) 265-0284

Primary Research Area

  • Mechanical Properties and Materials for Extreme Conditions

Professional Highlights

  • Professor Bellon received an electrical engineering degree from Ecole Superieure d'Electricite (France) in 1984 and a PhD in materials science from University Paris 6 (France) in 1989. He then worked at the Physical Metallurgy Research Section (SRMP) at the CEA Center for Research at Saclay (France) until 1996. He first worked in the MatSE Department at UIUC as a post-doctoral fellow in 1993-1994, and joined the faculty at UIUC in 1996. He received an NSF Career Award in 1998, awards from the Academy for Excellence in Engineering Education (University of Illinois) in 1998, 1999 and 2000 and the Don Burnett Teaching Award in 2000.

Research Statement

My research program is mainly focused on alloys or mixtures submitted to a sustained external forcing: such conditions are often met during either the processing of materials (e.g. by ball-milling or during thin film growth) or during the use of these materials (e.g. during frictional wear or under irradiation). Alloys in such environments have been termed "driven alloys." When the intensity of the forcing is high enough, non-equilibrium phases or microstructures can develop. From a practical point of view, these driving forces can have deleterious effects on the properties of materials: for instance precipitates can be dissolved,leading to a loss of mechanical strength. On the other hand, non-equilibrium processing can provide new routes to synthesizing novel materials: e.g., extended solid solutions or functional nanocomposites can be obtained by processing powders with high-energy ball milling or by processing thin films with energetic ion beams.

The related facet of our research is on the kinetic evolution of alloys during heat treatments. We are taking advantage of the kinetic models developed for driven alloys to study diffusion phenomena and diffusion-controlled reactions such as nucleation, growth and coarsening in complex alloys.

We are performing experiments, atomic computer simulations (kinetic Monte Carlo and molecular dynamics) and analytical modeling of these nonequilibrium alloys. The experiments carried out in our laboratory include ball-milling, wear testing, ion and laser irradiation (in collaboration with Prof. Averback). Materials are characterized by using the facilities available at the National User Facility at the Materials Research Laboratory. These include SEM, TEM, HRTEM, DSC and X-ray diffraction. Computer simulations are run on our cluster of LINUX workstations, and at computation centers on campus (MRL-MCC, MRL-CFC).

Research Areas

  • Computational Material Science
  • Metals

Research Topics

Selected Articles in Journals

  • K. Sastry, D. D. Johnson, D. E. Goldberg, and P. Bellon, "Genetic programming for multiscale modeling," Inter. J. Multiscale Comp. Eng., Vol 2, pp. 239-256 (2004).
  • R. A. Enrique and P. Bellon, "Nonequilibrium fluctuations, effective temperature, and effective interactions driven by irradiation of alloys," Physical Review B, Vol 70, pp. 224106 (2004).
  • Jia Ye and P. Bellon, "Nanoscale patterning of chemical order induced by displacement cascades in irradiated alloys. II. Analytical modeling," Physical Review B, Vol 70, pp. 094105 (2004).
  • Jia Ye and P. Bellon, "Nanoscale patterning of chemical order induced by displacement cascades in irradiated alloys. I. A kinetic Monte Carlo study," Phys. Rev. B, 70, 094104 (2004).
  • J. D. Hahn, Fang Wu, P. Bellon, " Cr-Mo solid solutions forced by high-energy ball milling," Metall. Mater. Trans. A, Vol 35, pp. 1105 (2004).
  • P. Bhattacharya, P. Bellon, R. S. Averback, S. J. Hales, "Nanocrystalline TiAl powders synthesized by high-energy ball milling: effects of milling parameters on yield and contamination," J. Alloys and Compounds, Vol 368, pp. 187-196 (2004).
  • P. Bellon, R. S. Averback, "Preface to viewpoint set on: materials under driving forces," Scripta Mater., Vol 49, pp. 921 (2003).
  • J. Ye, Ji-wen Liu, R. Enrique, P. Bellon, " Compositional and order patterning in driven alloys: the role of external-forcing characteristic lengths," Scripta Mater., Vol 49, pp. 969 (2003).
  • R. Enrique, K. Nordlund, R. S. Averback, P. Bellon, " Simulations of dynamical stabilization of Ag-Cu nanocomposites by ion-beam processing," J. Appl. Phys., Vol 93, pp. 2917 (2003).
  • P. Bellon, G. Martin, "Coupled relaxation of concentration and order fields in the linear regime," Physical Review B, Vol 66, pp. 184208 (2002).
  • S. Zghal, M. J. H￿tch, J.-P. Chevalier, R. Twesten, F. Wu, P. Bellon , "Electron microscopy nanoscale characterization of ball-milled Cu-Ag powders. Part I: Solid solution synthesized by cryo-milling," Acta Mater., Vol 50, pp. 4695 (2002).
  • J. Liu, P. Bellon, "Patterning and ordering in driven alloys with coupled conserved and nonconserved order parameters," Physical Review B, Vol 66, pp. 020303(R) (2002).
  • J.-M. Roussel, P. Bellon, " Self-diffusion and solute diffusion in alloys under irradiation: Influence of ballistic jumps," Physical Review B, Vol 65, pp. 144107 (2002).
  • R. Enrique, F. Wu, P. Bellon, "A new approach for the direct synthesis of nanocomposite thin films by ion-beam processing," Surface Coatings and Technology, Vol 150, pp. 1 (2002).
  • R. Enrique and P. Bellon, "Self-organized Cu-Ag nanocomposites synthesized by intermediate temperature ion-beam mixing," Applied Physics Letters, Vol 78, pp. 4178-4180 (2001).
  • J.-M. Roussel, P. Bellon, "Vacancy-assisted phase separation with asymmetric atomic mobility: coarsening rates, precipitate compositions and morphologies," Physical Review B, Vol 63, pp. 184114 (2001).
  • R. Enrique and P. Bellon, ￿Compositional patterning in immiscible alloys driven by irradiation,￿ Physical Review B, Vol 63, pp. 134111 (2001).
  • Fang Wu, P. Bellon, T. Lusby and A. Melmed, ￿Forced mixing and nanoscale decomposition in ball-milled Cu-Ag characterized by APFIM,￿ Acta Materialia, Vol 49, pp. 453 (2001).
  • D. Le Floc￿h, P. Bellon and M. Athenes, ￿Slow coarsening of B2 ordered domains at low temperatures: a kinetic Monte Carlo study,￿ Physical Review B, Vol 62, pp. 3142 (2000).
  • R. Enrique and P. Bellon, ￿Compositional patterning in systems driven by competing dynamics with different lengthscale,￿ Phys. Rev. Lett., Vol. 84, 2885 (2000).
  • M. Athenes, P. Bellon and G. Martin, ￿Effects of atomic mobilities on phase separation kinetics: a Monte-Carlo study,￿ Acta Materialia, Vol 48, pp. 2675 (2000).

Teaching Honors

  • Stanley H. Pierce Faculty Award (2009)
  • Multi-year Faculty Achievement Award (2007)
  • Outstanding Advisors' List (2006)
  • Collins Fellow Award (2000)
  • Burnett Teaching Award (2000)
  • GE Fellow Award (1999)
  • GE Scholar Award (1998)

Research Honors

  • NSF CAREER Award (1998)