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Sergio Lozano-Perez

Professor Sergio Lozano-Perez
George Kelley Professor of Materials
St Edmund Hall

Department of Materials
University of Oxford
16 Parks Road
Oxford OX1 3PH
UK

Tel: +44 1865 273795 (Room 154.30.06)
Tel: +44 1865 273777 (reception)
Fax: +44 1865 273789 (general fax)

Nanoanalysis Group

Summary of Interests

1.    Understanding the mechanisms controlling the initiation and propagation of Stress Corrosion Cracks in steels from nuclear reactors
2.    Characterization of ODS steels for fusion reactors
3.    Application of Multivariate Statistical Analysis to Microanalysis
4.    Improving the acquisition and processing of analytical data: EFTEM, EELS-SI and EDX-SI

Current Research Projects

Atomic scale characterization of ODS steels
Dr. V. de Castro, Dr. S. Lozano-Perez
ODS FeCr steels have been chosen as blanket materials for the new ITER experimental fusion reactor. Their optimum mechanical and corrosion behaviour relies on a fine dispersion of Y2O3 precipitates which is challenging to characterize. Cs-corrected EFTEM and 3D atom-probe have been used successfully to detect and analyze precipitates as small as 1nm in diameter.

Radiation damage mechanisms in Nuclear Materials
A. London, Dr. S. Lozano-Perez, Prof. C. Grovenor
Radiation damage is a major degradation mechanism in materials in nuclear reactors, affecting both the mechanical properties and the rate of chemical reactions.  This project uses state-of-the-art analytical techniques to study radiation damage mechanisms in model corrosion-resistant ODS alloys processed by our partners in IGCAR in Kalpakkam and in the Key Laboratory of Materials Physics, Chinese Academy of Sciences, Hefei. We will use ion beam implantation as a proxy for neutron damage to study how the chemistry and structure of the ODS phases change as a function of dose and temperature.  Funded by EPSRC grant EP/M017540/1.

2 public active projects

Research Publications

1. Borrego, J. M. et al. Structural relaxation in Fe(Co)SiAlGaPCB amorphous alloys. J Alloys Compd 584, 607-610 (2014).

2. De Castro, V., Rodrigo, P., Marquis, E. A. & Lozano-Perez, S. Oxide dispersion strengthened Fe-12Cr steel in three dimensions: An electron tomography study. J Nucl Mater 444, 416-420 (2014).

3. Ribis, J. & Lozano-Perez, S. Nano-cluster stability following neutron irradiation in MA957 oxide dispersion strengthened material. J. Nucl. Mater. 444, 314-322 (2014).

4. Blázquez, J. S., Ipus, J. J., Lozano-Pérez, S. & Conde, A. Metastable soft magnetic materials produced by mechanical alloying: Analysis using an equivalent time approach. JOM 65, 870-882 (2013).

5. Dugdale, H., Armstrong, D. E. J., Tarleton, E., Roberts, S. G. & Lozano-Perez, S. How oxidized grain boundaries fail. Acta Mater 61, 4707-4713 (2013).

6. Ipus, J. J., Blázquez, J. S., Franco, V., Lozano-Pérez, S. & Conde, A. Role of starting phase of boron on the mechanical alloying of FeNbB composition. J Alloys Compd 553, 119-124 (2013).

7. Knappett, B. R. et al. Characterisation of Co@Fe3O4 core@shell nanoparticles using advanced electron microscopy. Nanoscale 5, 5765-5772 (2013).

8. Kruska, K. et al. Atom-probe tomography of surface oxides and oxidized grain boundaries in alloys from nuclear reactors (2012 MRS Fall Meeting Ser. 1514, 2013).

9. Marceau, R. K. W. et al. Multi-scale correlative microscopy investigation of both structure and chemistry of deformation twin bundles in Fe-Mn-C steel. Microsc. Microanal. 19, 1581-1585 (2013).

10. Schreiber, D. K. et al. Examinations of oxidation and sulfidation of grain boundaries in alloy 600 exposed to simulated pressurized water reactor primary water. Microsc. Microanal. 19, 676-687 (2013).

11. Tong, M. et al. Multiscale, multiphysics numerical modeling of fusion welding with experimental characterization and validation. JOM 65, 99-106 (2013).

12. Yardley, S. S. et al. An investigation of the oxidation behaviour of zirconium alloys using isotopic tracers and high resolution SIMS. J. Nucl. Mater. 443, 436-443 (2013).

13. Blázquez, J. S., Borrego, J. M., Conde, C. F., Conde, A. & Lozano-Pérez, S. Extension of the classical theory of crystallization to non-isothermal regimes: Application to nanocrystallization processes. J Alloys Compd 544, 73-81 (2012).

14. de Castro, V. et al. Analytical characterisation of oxide dispersion strengthened steels for fusion reactors. Energy Mater. Mater. Sci. Eng. Energy Syst. 6, 719-723 (2012).

15. E, H., Nellist, P. D., Lozano-Perez, S. & Ozkaya, D. Quantitative analysis of core-shell catalyst nanoparticles for industrial applications. J. Phys. Conf. Ser. 371 (2012).

16. Grovenor, C. R. M. et al. Mechanisms of oxidation of fuel cladding alloys revealed by high resolution APT, TEM and SIMS analysis (2011 MRS Fall Meeting Ser. 1383, 2012).

17. Grovenor, C. R. M. et al. 3D visualisation of crack distributions in oxidised zirconium alloys by FIB-slicing (2011 MRS Fall Meeting Ser. 1421, 2012).

18. Kruska, K. et al. Nanoscale characterisation of grain boundary oxidation in cold-worked stainless steels. Corros. Sci. 63, 225-233 (2012).

19. Lozano, J. G. et al. (S)TEM analysis of the interdiffusion and barrier layer formation in Mn/Cu heterostructures on SiO 2 for interconnect technologies. J. Phys. Conf. Ser. 371 (2012).

20. Lozano-Perez, S., Kruska, K., Iyengar, I., Terachi, T. & Yamada, T. Understanding surface oxidation in stainless steels through 3D FIB sequential sectioning. J. Phys. Conf. Ser. 371 (2012).

21. Lozano-Perez, S., Kruska, K., Iyengar, I., Terachi, T. & Yamada, T. The role of cold work and applied stress on surface oxidation of 304 stainless steel. Corros. Sci. 56, 78-85 (2012).

22. Ni, N. et al. How the crystallography and nanoscale chemistry of the metal/oxide interface develops during the aqueous oxidation of zirconium cladding alloys. Acta Mater 60, 7132-7149 (2012).

23. Ni, N., Lozano-Perez, S., Sykes, J. & Grovenor, C. Multi-scale characterisation of oxide on zirconium alloys. Mater High Temp 29, 166-170 (2012).

24. Ribis, J. & Lozano-Perez, S. Orientation relationships and interface structure of α′-Cr nanoclusters embedded in α-Fe matrix after α-α′ Demixing in neutron irradiated Oxide Dispersion Strengthened material. Mater Lett 74, 143-146 (2012).

25. De Castro, V., Leguey, T., Auger, M. A., Lozano-Perez, S. & Jenkins, M. L. Analytical characterization of secondary phases and void distributions in an ultrafine-grained ODS Fe-14Cr model alloy. J. Nucl. Mater. 417, 217-220 (2011).

26. De Castro, V. et al. Analytical characterisation of oxide dispersion strengthened steels for fusion reactors. Mater. Sci. Technol. 27, 719-723 (2011).

27. De Castro, V., Marquis, E. A., Lozano-Perez, S., Pareja, R. & Jenkins, M. L. Stability of nanoscale secondary phases in an oxide dispersion strengthened Fe-12Cr alloy. Acta Mater 59, 3927-3936 (2011).

28. Kruska, K. et al. 3D atom-probe characterization of stress and cold-work in stress corrosion cracking of 304 stainless steel (15th International Conference on Environmental Degradation of Materials in Nuclear Power Systems-Water Reactors 2011 Ser. 2, 2011).

29. Lozano, J. G. et al. Interdiffusion and barrier layer formation in thermally evaporated Mn/Cu heterostructures on SiO2 substrates. Appl. Phys. Lett. 98 (2011).

30. Lozano-Perez, S. et al. Characterizing environmental degradation in PWRs by 3D FIB sequential sectioning (15th International Conference on Environmental Degradation of Materials in Nuclear Power Systems-Water Reactors 2011 Ser. 2, 2011).

31. Lozano-Perez, S., Rodrigo, P. & Gontard, L. C. Three-dimensional characterization of stress corrosion cracks. J. Nucl. Mater. 408, 289-295 (2011).

32. Marquis, E. A., Lozano-Perez, S. & Castro, V. D. Effects of heavy-ion irradiation on the grain boundary chemistry of an oxide-dispersion strengthened Fe-12 wt.% Cr alloy. J. Nucl. Mater. 417, 257-261 (2011).

33. Ni, N., Lozano-Perez, S., Sykes, J. & Grovenor, C. Quantitative EELS analysis of zirconium alloy metal/oxide interfaces. Ultramicroscopy 111, 123-130 (2011).

34. Ni, N., Lozano-Perez, S., Sykes, J. M., Smith, G. D. W. & Grovenor, C. R. M. Focussed ion beam sectioning for the 3D characterisation of cracking in oxide scales formed on commercial ZIRLO™ alloys during corrosion in high temperature pressurised water. Corros. Sci. 53, 4073-4083 (2011).

35. Preuss, M. et al. Studies regarding corrosion mechanisms in zirconium alloys. J. ASTM Int. 8 (2011).

36. Preuss, M. et al. Studies regarding corrosion mechanisms in zirconium alloys (16th International Symposium on Zirconium in the Nuclear Industry Ser. 1529 STP, 2011).

37. Robertson, I. M. et al. Towards an integrated materials characterization toolbox. J. Mater. Res. 26, 1341-1383 (2011).

38. Shih, S. -., Herrero, P. R., Li, G., Chen, C. -. & Lozano-Perez, S. Characterization of mesoporosity in ceria particles using electron microscopy. Microsc. Microanal. 17, 54-60 (2011).

39. Speller, S. C. et al. Analysis of local chemical and structural inhomogeneities in Fe ySe 1-xTe x single crystals. Appl. Phys. Lett. 99 (2011).

40. E, H., Nellist, P. D., Lozano-Perez, S. & Ozkaya, D. Towards quantitative analysis of core-shell catalyst nano-particles by aberration corrected high angle annular dark field STEM and EDX. J. Phys. Conf. Ser. 241 (2010).

41. Hong, S. Y. et al. Filled and glycosylated carbon nanotubes for in vivo radioemitter localization and imaging. Nat. Mater. 9, 485-490 (2010).

42. Ipus, J. J., Blázquez, J. S., Conde, A. & Lozano-Pérez, S. Microstructural characterization by TEM techniques of mechanically alloyed FeNbGe powders. J Alloys Compd 505, 86-90 (2010).

43. Lozano-Perez, S., Saxey, D. W., Yamada, T. & Terachi, T. Atom-probe tomography characterization of the oxidation of stainless steel. Scripta Mater 62, 855-858 (2010).

44. Ni, N. et al. Porosity in oxides on zirconium fuel cladding alloys, and its importance in controlling oxidation rates. Scripta Mater 62, 564-567 (2010).

45. Shin, S. -., Lozano-Perez, S. & Cockayne, D. J. H. Investigation of grain boundaries for abnormal grain growth in polycrystalline SrTiO3. J. Mater. Res. 25, 260-265 (2010).

46. Weigand, M. et al. Individual grain boundary properties and overall performance of metal-organic deposition coated conductors. Phys. Rev. B Condens. Matter Mater. Phys. 81 (2010).

47. de Castro, V. et al. Microstructural characterization of Y2O3 ODS-Fe-Cr model alloys. J. Nucl. Mater. 386-388, 449-452 (2009).

48. De Castro, V., Lozano-perez, S. & Jenkins, M. L. Effects of ion irradiation on the microstructure of an ODS/Fel2Cr alloy (2008 MRS Fall Meeting Ser. 1125, 2009).

49. Hudson, D. et al. The atomic scale structure and chemistry of the zircaloy-4 metal-oxide interface (714th International Conference on Environmental Degradation of Materials in Nuclear Power Systems Water Reactors 2009 Ser. 2, 2009).

50. Ipus, J. J., Blázquez, J. S., Lozano-Perez, S. & Conde, A. Microstructural evolution characterization of Fe-Nb-B ternary systems processed by ball milling. Philos. Mag. 89, 1415-1423 (2009).

51. Lozano-Perez, S., de Castro Bernal, V. & Nicholls, R. J. Achieving sub-nanometre particle mapping with energy-filtered TEM. Ultramicroscopy 109, 1217-1228 (2009).

52. Lozano-Perez, S., Saxey, D., Terachi, T., Yamada, T. & Cervera-Gontard, L. 3-D characterization of SCC in cold worked stainless steels (714th International Conference on Environmental Degradation of Materials in Nuclear Power Systems Water Reactors 2009 Ser. 2, 2009).

53. Lozano-Perez, S., Saxey, D. W., Marquis, E. A., Terachi, T. & Yamada, T. Atom-probe tomography of surface oxides in a 20% cold worked stainless steel tested under pwr primary water conditions. Microsc. Microanal. 15, 304-305 (2009).

54. Lozano-Perez, S. et al. Multi-scale characterization of stress corrosion cracking of cold-worked stainless steels and the influence of Cr content. Acta Mater 57, 5361-5381 (2009).

55. Marquis, E. A. et al. Nuclear reactor materials at the atomic scale. Mater. Today 12, 30-37 (2009).

56. Marquis, E. A., Lozano-Perez, S. & De Castro, V. Grain boundary chemistry before and after ion implantation in ODS steels. Microsc. Microanal. 15, 270-271 (2009).

57. Millán, M. et al. Preferential Co partitioning to α-Fe in nanocrystalline CoFeNbB alloys by Mn addition. J. Non Cryst. Solids 355, 109-113 (2009).

58. Odette, G. R. et al. Atom-probe tomography, small angle neutron scattering, transmission electron microscopy, positron annihilation spectroscopy and x-ray absorption spectroscopy characterization of nano-scale features in nanostructured ferritic alloys. Microsc. Microanal. 15, 244-245 (2009).

59. Blázquez, J. S. et al. Nanocrystallization effects on the specific heat of Fe-Co-Nb-B amorphous alloy. J. Non Cryst. Solids 354, 5135-5137 (2008).

60. Lozano-Perez, S. Improving EFTEM data using multivariate statistical analysis. J. Phys. Conf. Ser. 126 (2008).

61. Lozano-Perez, S. Novel characterization of stress corrosion cracks. J. Phys. Conf. Ser. 126 (2008).

62. Lozano-Perez, S. A guide on FIB preparation of samples containing stress corrosion crack tips for TEM and atom-probe analysis. Micron 39, 320-328 (2008).

63. Lozano-Perez, S., English, C. A., Terachi, T. & Yamada, T. A multi-scale approach to stress corrosion cracking. NACE - Int. Corros. Conf. Ser. (2008).

64. Lozano-Perez, S., English, C. A., Terachi, T. & Yamada, T. A multi-scale approach to stress corrosion cracking. NACE - Int. Corros. Conf. Ser., 084951-084959 (2008).

65. Lozano-Perez, S. & Gontard, L. C. Understanding stress corrosion cracking with electron tomography. Microsc. Microanal. 14, 642-643 (2008).

66. Lozano-Perez, S. et al. High-resolution imaging of complex crack chemistry in reactor steels by NanoSIMS. J. Nucl. Mater. 374, 61-68 (2008).

67. Lozano-Perez, S. et al. Using NanoSIMS to map trace elements in stainless steels from nuclear reactors. Appl. Surf. Sci. 255, 1541-1543 (2008).

68. Cerezo, A. et al. Atom probe tomography today. Mater. Today 10, 36-42 (2007).

69. Cerezo, A. et al. Overview: Recent progress in three-dimensional atom probe instruments and applications. Microsc. Microanal. 13, 408-417 (2007).

70. Lozano-Perez, S. & Titchmarsh, J. M. EFTEM assistant: A tool to understand the limitations of EFTEM. Ultramicroscopy 107, 313-321 (2007).

71. Lozano-Perez, S., Jenkins, M. L. & Titchmarsh, J. M. Evidence for deformation-induced transformations of Cu-rich precipitates in an aged FeCu alloy. Philos Mag Lett 86, 367-374 (2006).

72. Lozano-Perez, S. et al. Comparison of the number densities of nanosized Cu-rich precipitates in ferritic alloys measured using EELS and EDX mapping, HREM and 3DAP. J. Mater. Sci. 41, 2559-2565 (2006).

73. Lozano-Perez, S., Titchmarsh, J. M. & Jenkins, M. L. Quantitative EFTEM measurement of the composition of embedded particles. J. Mater. Sci. 41, 4394-4404 (2006).

74. Lozano-Perez, S., Titchmarsh, J. M. & Jenkins, M. L. Determination of the Fe content of embedded Cu-rich particles in ferritic alloys using energy-filtered TEM. Ultramicroscopy 106, 75-91 (2006).

75. Cizek, P., McKay, B. J. & Lozano-Perez, S. Investigation of the interfaces between boride particles and aluminium in the as-received and re-melted Ti-B-Al grain refiner master alloy (Electron Microscopy and Analysis 2003 - Proceedings of the Institute of Physics Electron Microscopy and Analysis Group Conference Ser. 179, 2004).

76. Lozano-Perez, S., Titchmarsh, J. M. & Jenkins, M. L. TEM characterization of stress corrosion cracks in 304SS (Electron Microscopy and Analysis 2003 - Proceedings of the Institute of Physics Electron Microscopy and Analysis Group Conference Ser. 179, 2004).

77. Lozano-Perez, S., Titchmarsh, J. M. & Jenkins, M. L. Energy-filtered imaging of Cu-nanoprecipitates (Electron Microscopy and Analysis 2003 - Proceedings of the Institute of Physics Electron Microscopy and Analysis Group Conference Ser. 179, 2004).

78. Lozano-Perez, S. & Titchmarsh, J. M. TEM investigations of intergranular stress corrosion cracking in austenitic alloys in PWR environmental conditions. Mater High Temp 20, 573-579 (2003).

79. Blázquez, J. S., Lozano-Pérez, S. & Conde, A. A study of the fcc (FeCo)23B6 phase in fully crystallized Fe-Co-Nb-B-Cu alloys. Philos Mag Lett 82, 409-417 (2002).

80. Huang, Y. Z., Lozano-Perez, S., Langford, R. M., Titchmarsh, J. M. & Jenkins, M. L. Preparation of transmission electron microscopy cross-section specimens of crack tips using focused ion beam milling. J. Microsc. 207, 129-136 (2002).

81. Langford, R. M., Huang, Y. Z., Lozano-Perez, S., Titchmarsh, J. M. & Petford-Long, A. K. Preparation of site specific transmission electron microscopy plan-view specimens using a focused ion beam system. J Vac Sci Technol B Microelectron Nanometer Struct 19, 755-758 (2001).

82. Blázquez, J. S., Lozano-Pérez, S. & Conde, A. Enthalpy and Curie temperature relaxation effects in FeSiB-CuNb alloys prepared at different quenching rates. Mater Lett 45, 246-250 (2000).