Research Interests

A/P. Zhang's research is concerned with mechanical properties of solid materials and structures, focusing on the evolution of the microstructures of a deformable solid and the atomistic processes of material deformation, evolution and failure.

1) Mechanical properties of solid materials and structures, focusing on the evolution of the microstructures, such as grain boundaries, dislocations and cracks,  and the atomistic processes of material deformation, evolution and failure;   

2) Mechanical behavior of soft matter, such as membranes, gels and cells, focusing on their swelling, instability and adhesion;  

3) Mechanical properties of low dimensional nanostructures such as carbon nanotubes and graphene, focusing on their instability, functionalization and edge effects.

Additional information:

A/P. Zhang was awarded the 2002 Singapore High Performance Computing Quest: The Blue Challenge Silver Award and the 2004 Singapore High Performance Computing Quest: The Blue Challenge Gold Award. He is the author or co-author of over 60 articles on fracture mechanics, computational mechanics, dislocation theory, mechanics of thin films and carbon nanotubes, and indentation mechanics.

1. Q.H. Cheng, P. Liu, H.J. Gao, Y.W. Zhang, “A computational modeling for micropipette-manipulated cell detachment from a substrate mediated by receptor-ligand binding”, J. Mech. Phys. Solids, (2008) (in press).
   
   
2. P. Liu, Y.W. Zhang, H. Yu,  X. Zhang, Q. H. Cheng, C. Lu, and W. Bonfield, “ Spreading of an anchorage dependent cell on a selectively ligand-coated substrate mediated by receptor-ligand binding”. J. Biomed. Mater. Res. A (2008) (in press)

3. V.B. Shenoy, C.D. Reddy, A. Ramasubramaniam, and Y.W. Zhang, “Edge-stress-induced warping of graphene sheets and nanoribbons”  Phys. Rev. Lett.  245501, (2008).
   
   
4. P. Liu, Y.W. Zhang, H.J. Gao, C. Lu, “Energetics and stability of C-60 molecules encapsulated in carbon nanotubes” Carbon  46(4),  649-655   (2008).
   
   
5. D.H. Kim, J. Song, W.M. Choi, H.S. Kim, .H. Kim, Z.J. Liu, Y. Huang, K.C. Hwang, Y.W. Zhang and J.A. Rogers, “Materials and noncoplanar mesh designs for integrated circuits with linear elastic responses to extreme mechanical deformations”  PNAS, 105, 18675-18680 (2008).
   
   
6. P. Liu, H.J. Gao, Y.W. Zhang, “Effect of defects on oscillation characteristics and instability of carbon nanotube-based oscillators” Appl. Phys. Lett. 93(8), 083107  (2008).
   
   
7. P. Liu, Y.W. Zhang, “Formation of surface structures of a heteroepitaxial film via controlled nucleation and cooperative propagation”  J. Phys. D: Appl. Phys. 41(22) 225303  (2008).
   
   
8. W.F. Wu, C.Y. Zhang, Y.W. Zhang, Y. Li, “Stress gradient enhanced plasticity in a monolithic bulk metallic glass”  Intermetallics  16(10), 1190-1198  (2008).
   
   
9. P. Liu, H.J. Gao, Y.W. Zhang, “Spontaneous generation and propagation of transverse coaxial traveling waves in multiwalled carbon nanotubes”  Appl. Phys. Lett. 93(1), 013106  (2008).
   
   
10. P. Liu, Y.W. Zhang, C. Lu, K.Y. Lam, “Three-dimensional analysis of the guided-assembled growth of heteroepitaxial islands on imperfectly pre-patterned surfaces”  Nanotechnology 19(18),  185302  (2008).
    
    
11. C.Y. Zhang and Y.W. Zhang,  “Computational analysis of adhesion force in the indentation of cells using atomic force microscopy” Phys. Rev. E 77, 021912 (2008).
    
    
12. Z.Y. Liu, G.S. Yi, H.T. Zhang, J. Ding, Y.W. Zhang, and J.M. Xue, A new type of multifunctional silica-coated nanocomposites, detectable by their upconversion fluorescence and addressable by a magnetic field” Chem. Comm. 6, 694-696 (2008).
    
    
13. C. Zheng and Y.W. Zhang. “A molecular dynamics study of the effect of voids on the deformation behavior of nanocrystalline copper” J. Nanomater. 64589 (2007).
    
    
14. G.K.L Goh, K.Y.S. Chan, B.S.K. Tan, Y.W. Zhang, J.H. Kim and T. Osipowicz, “Low-temperature epitaxy of KTaO3 and KNbO3” J.  Electrochem. Soc. 55(1), D53-D56 (2008).
    
    
15. P. Liu, Y.W. Zhang, H.J. Gao, and K.Y. Lam, “Sustained surface wave propagation induced by surface diffusion driven by strain relaxation in a heteroepitaxial film”
    Appl. Phys. Lett. 92(6), 06913 (2008).
    
    
16. P. Liu, C. Lu, Y.W. Zhang, K.Y. Lam, “Heteroepitaxial growth of quantum wire arrays through prepatterning substrate surfaces” Appl. Phys. Lett. 91 (9), 093129 (2007).
    
    
17. P. Liu, C. Lu and Y.W. Zhang, “Formation of surface structures during heteroepitaxial thin film growth on prepatterned substrates” Phys. Rev. B 76 (8), 085336 (2007).
    
    
18. C. Y. Zhang and Y.W. Zhang, “Effects of membrane pre-stress and intrinsic viscoelasticity on nanoindentation of cells using AFM” Philos. Mag. 87 (23), 3415-3435 (2007).
    
    
19. P. Liu, Y.W. Zhang, Q.H. Cheng, C. Lu, “Simulations of the spreading of a vesicle on a substrate surface mediated by receptor-ligand binding” J. Mech. Phys. Solids 55(6), 1166-1181 (2007).
    
    
20. C. K. Chia, Y.W. Zhang, S.S. Wong, A.M. Yong, S.Y. Chow, S.J. Chua, J. Guo, “Saturated dot density of InAs/GaAs self-assembled quantum dots grown at high growth rate” Appl. Phys. Lett. 90 (16), 161906 (2007).
    
    
21. P. Liu, Y.W. Zhang, K.Y. Zeng, C. Lu and K.Y. Lam, “Finite element analysis of interface delamination and buckling in thin film systems by wedge indentation” Eng. Fract. Mech. 74 (7), 1118-1125 (2007).
    
    
22. P. Liu, Y.W. Zhang, Morphological evolution of heteroepitaxial islands during Stranski-Krastonov growth. Int. J. Solids and Structures 44 (6): 1733-1744 (2007).
    
    
23. P. Liu, Y.W. Zhang, C. Lu,  “Phase diagrams for growing ordered heteroepitaxial quantum dots and quantum rings by surface prepatterning” Appl. Phys. Lett. 90 (7), 071905 (2007).
    
    
24. S.S. Quek, Z.X. Wu, Y.W. Zhang, Y. Xiang, D.J. Srolovitz, “Dislocation junctions as barriers to threading dislocation migration” Appl. Phys. Lett. 90 (1): Art. No. 011905 (2007).
    
    
25. C.Y. Zhang, Y.W. Zhang, K.Y. Zeng, L. Shen, Y.Y. Wang, “Extracting the elastic and viscoelastic properties of a polymeric film using a sharp indentation relaxation test” J. Mater. Res.21 (12): 2991-3000 (2006).
    
    
26. L. Wang, K. Wang, L. Chen, Y.W. Zhang, C.B. He. “Preparation, morphology and thermal/mechanical properties of epoxy/nanoclay composite” Composites A. 37 (11): 1890-1896 2006.
    
    
27. C.Y. Zhang, Y.W. Zhang, K.Y. Zeng, L. Shen, “Characterization of mechanical properties of polymers by nanoindentation tests” Phil. Mag. 86 (28): 4487-4506 (2006).
    
    
28. S. S. Quek, Y. Xiang, Y. W. Zhang, D. J. Srolovitz and C. Lu, “Level set simulation of dislocation dynamics in thin films” Acta Mater.54 (9): 2371-2381 (2006).
    
    
29. C. Zheng and Y.W. Zhang, “Atomistic simulations of mechanical deformation of high-angle and low-angle  nanocrystalline copper at room temperature”  Mater. Sci. Eng. A, 423 (1-2): 97-101 (2006).
    
    
30. L. Wang, K. Wang, L. Chen, C.B. He, L. Wang and Y.W. Zhang,  “Hydrothermal effects on the thermomechanical properties of high performance epoxy/clay nanocomposites” Polymer Eng.  Sci. 46 (2): 215-221 (2006).
    
    
31. P. Liu, Y.W. Zhang and C. Lu,  “Anisotropy effect on heteroepitaxial growth of self-assembled islands” Appl. Phys. Lett. 88 (4): 041922 (2006).
    
    
32. P. Liu, Y.W. Zhang and C. Lu, “Analysis of the oscillatory behavior of double-walled carbon nanotube-based oscillators” Carbon44 (1): 27-36 (2006).
    
    
33. P. Liu, Y.W. Zhang and C. Lu,  “Structures and stability of defect-free multiwalled carbon toroidal rings”  J. Appl. Phys. 98(11): 113522 (2005).
34. P. Liu, Y.W. Zhang, C. Lu, “Atomistic simulations of formation and stability of carbon nanorings”  Phys. Rev. B 72 (11): 115408 (2005).
    
    
35. Y.W. Zhang, “Surface stability and evolution of biaxially strained epitaxial thin films” Appl. Phys. Lett. 87 (12): 121916 (2005).
    
    
36. P. Liu, Y.W. Zhang and C. Lu, “Oscillatory behavior of gigahertz oscillators based on multiwalled carbon nanotubes” J. Appl. Phys. 98 (1): 014301 (2005).
    
    
37. C.Y. Zhang, Y.W. Zhang, K.Y. Zeng and L. Shen, “Nanoindentation of polymers with a sharp indenter” J. Mater. Res. 20(6), 1597-1605 (2005).
    
    
38. P. Liu, Y.W. Zhang and C. Lu, “Oscillatory behavior of C60-nanotube oscillators: A molecular dynamics study”, J. Appl. Phys. 97(9), 094313 (2005).
    
    
39. Z.L. Miao, Y.W. Zhang, S.J. Chua, Y.H. Chye, P. Chen and S. Tripathy, “Optical properties of InAs/GaAs surface quantum dots”  Appl. Phys. Lett. 86(3), 031914 (2005).
    
    
40. K. Hbaieb and Y.W. Zhang, “A parametric study of a pressurized blister test for an elastic-plastic film-rigid substrate system” Mater. Sci.  Eng. A390(1-2), 385-392 (2005).
    
    
41. Y.W. Zhang, P. Liu and C. Lu, “Molecular dynamics simulations of the preparation and deformation of nanocrystalline copper” Acta Mater. 52(17), 5105-5114 (2004).
    
    
42. C.Y. Zhang, Y.W. Zhang and K.Y. Zeng, “Extracting the mechanical properties of a viscoelastic polymeric film on a hard elastic substrate” J. Mater. Res. 19(10), 3053-3061 (2004).
    
    
43. P. Liu, Y.W. Zhang and C. Lu, “Molecular dynamics simulations of bending behavior of tubular graphite cones” Appl. Phys. Lett. 85(9) 1778 (2004).
    
    
44. P. Liu and Y.W. Zhang, C. Lu and K.Y. Lam, “Tensile and bending properties of double-walled carbon nanotubes” J. Phys. D: Appl. Phys. 37(17) 2358-2363 (2004).
    
    
45. Y.W. Zhang and D. J. Srolovitz, “Surface instability and evolution of nonlinear elastic heteroepitaxial thin film structures, Phys. Rev. B 70(4), 041402(R).
    
    
46. S. Yang, Y.W. Zhang and K.Y. Zeng, “Analysis of nanoindentation creep for polymeric materials” J. Appl. Phys. 95(7), 3655-3666 (2004).
    
    
47. P. Liu, Y.W. Zhang, B. Box and C. Lu, “Molecular dynamics study of dislocation formation in a [001] face-cenetered-cubic epitaxial island under tensile stress” Appl. Phys. Lett. 84(5), 714-716 (2004).
    
    
48. P. Liu, Y.W. Zhang, H.P. Lee and C. Lu, “Atomistic simulations of uniaxial tensile behaviors of single-walled carbon nanotubes” Molecular Simulation 30(8), 543-547 (2004).
    
    
49. P. Liu, Y.W. Zhang and C. Lu, “A three-dimensional concurrent atomstic/continuum analysis of an epitaxial strained island”  J. Appl. Phys. 94(10), 6350-6353 (2003).
    
    
50. P. Liu, Y.W. Zhang and C. Lu, “Three-dimensional finite element simulations of the self-organized growth of quantum dot superlattices” Phys. Rev. B 68(19), 195314 (2003).
    
    
51. P. Liu, Y.W. Zhang, C. Lu “Coarsening kinetics of heteroepitaxial islands in nucleationless Stranski-Krastanov growth” Phys. Rev. B  68(3)(10), 035402 (2003).
    
    
52. P. Liu, Y.W. Zhang and C. Lu, “Formation of self-assembled heteroepitaxial islands in elastically anisotropic films”,  Phys. Rev. B 67(16), 165414 (2003).
    
    
53. P. Liu, Y.W. Zhang, C. Lu, “Computer simulation of Stranski-Krastanov growth of heteroepitaxial film with elastic anisotropy”  Surface Science  526(3), 375-382 (2003).
    
    
54. Y.W. Zhang, A.F. Bower, and P. Liu, “Morphological evolution driven by strain induced surface diffusion” Thin Solid Films424(1), 9-14 (2003).
    
    
55. P. Liu, Y.W. Zhang and L. Cheng, “Interface Delamination in plastic IC packages induced by thermal loading  and vapor pressure – a micromechanics model”  IEEE Transaction on Advanced Packaging  26(1), 1-9 (2003).
    
    
56. P. Liu, Y.W. Zhang, and C. Lu, “Self-organized growth of quantum dot superlattices”  Appl. Phys. Lett.  80(21),  3910-3912 (2002).
    
    
57. T.C. Wang, Y.W. Zhang, and S.J. Chua, “Dislocation dynamics of strain relaxation in epitaxial layers”  J. Appl. Phys. 89(11),  6069-6072 (2001).
    
    
58. T.C. Wang, Y.W. Zhang, and S.J. Chua, “Dislocation evolution in epitaxial multilayers and graded composition buffers”  Acta Mater. 49(9), 1599-1605 (2001).
    
    
59. Y.W. Zhang, and A.F. Bower,  “Three-dimensional analysis of shape transitions in strained heteroepitaxial islands”  Appl. Phys. Lett.  78(18), 2706-2708 (2001).
    
    
60. P Liu, L. Cheng and Y.W. Zhang, “Measuring interface parameters and toughness- a micro-mechanics study” Acta  Mater.  49(5), 817-825 (2001).
    
    
61. P Liu, L. Cheng and Y.W. Zhang, “Interface toughness analysis of combined mode I, II and  III loadings under small scale yielding” Scripta Mater.  44, 487 (2001).
    
    
62. Y.W. Zhang, K.Y. Zeng and R. Thampuran “Interface delamination generated by indentation in thin film systems- a computational mechanics study” Mat Sci. & Eng. A 319, 893-897  (2001).
    
    
63. Y.W. Zhang, “Self-organization, shape transition, and stability of epitaxially strained islands”, Phys. Rev. B  61(15), 10388-10392 (2000).
64. Y.W. Zhang, “Effect of temperature and orientation on the stability of surfaces of stressed crystals” Phys. Rev. B  60(19) 13325-13327 (1999).
    
    
65. Y.W. Zhang, “Formation of epitaxially strained islands by controlled annealing” Appl. Phys. Lett. 75(2), 205-207 (1999).
    
    
66. Y.W. Zhang, S.J. Xu, and C. H. Chiu, “Vertical self-alignment of quantum dots in superlattice”  Appl. Phys. Lett. 74(13), 1809-1811 (1999).
    
    
67. Y.W. Zhang and A. F. Bower, “Numerical simulation of island formation in a coherent strained epitaxial thin film system”, J. Mech. Phys. Solids  47(11), 2273-2297, (1999).
    
    
68. Y.W. Zhang and A.F. Bower, “Three-dimensional simulations of island formation in a coherent strained epitaxial film” Thin Solid Films 357(1), 8-12 (1999).
    
    
69. Y.W. Zhang, A. F. Bower, L Xia, and C.F. Shih, “Three dimensional finite element analysis of the evolution of the voids and thin films by strain and electromigration induced surface diffusion”  J. Mech. Phys. Solids  47(1), 173-199 (1999).
    
    
70. T.C. Wang, K.R. Wang, and Y.W. Zhang, “A unified model for dislocation nucleation, dislocation emission and dislocation free zone” Int. J. Fracture78(3-4), 227-239  (1996).
    
    
71. Y.W. Zhang , T. C. Wang, “Molecular dynamics simulation of the interaction of a dislocation array from a crack tip with GBs”, Model. Simul. Mater. Sci. Eng.  4(2),  231-244  (1996).
    
    
72. Y.W. Zhang, T. C. Wang, “Lattice instability at a fast moving crack tip”,  J. Appl. Phys. 80(8), 4332-4336 (1996).
    
    
73. Y.W. Zhang and T.C. Wang, “Advances in molecular dynamics simulations of defect interactions in FCC single crystals” Adv. Mech. 26, 14 (1996).
    
    
74. Y.W. Zhang , T. C. Wang, and Q. H. Tang,  “Brittle and ductile fracture at the atomistic crack tip in copper crystals” Scripta Metal. Mater. 33(2), 267-274 (1995).
    
    
75. Y.W. Zhang , T. C. Wang, and Q. H. Tang, “The effect of thermal activation on dislocation processes at an atomistic crack tip”,  J Phys. D: Appl. Phys. 28(4), 748-754 (1995).
    
    
76. Y.W. Zhang , T. C. Wang, and Q. H. Tang, “Simulation of nucleation and emission of dislocations by molecular dynamics method”  J. Appl. Phys.  77(6), 2393-2399 (1995).
    
    
77. Y.W. Zhang , T. C. Wang, and Q. H. Tang, “On the unstable stacking criterion for ideal and cracked crystals”  Philos. Mag. A  72(4), 881-889  (1995) .
    
    
78. P. Liu, Y.W. Zhang, and K.D. Zhang, “Bending solution of high-order refined shear deformation theory for rectangular composite plates”, Int. J. Solids & Structures  31(18), 2491-2507 (1994).
    
    
79. P. Liu, Y.W. Zhang, and X.Z. Zhang, “An improved in-plane thermoelastic theory for laminated composite plates”, Int. J. Solids & Structures 31(20), 2867-2881 (1994).
    
    
    
80. P. Liu, Y.W. Zhang, and X.Z. Zhang, “Improved high-order thermoelastic response theory for analyzing thermal bending of laminated composite plates”, J. Therm. Stresses 17 (2), 163-190 (1994).
    
    
81. Y.W. Zhang , T. C. Wang, and N.G. Liang, “The inhomogeneity of plastic- deformation in ductile single crystals”, Model. Simul. Mater. Sci. Eng.  2(6), 1171-1193 (1994).