From: engp1058@nuscc.nus.sg (Lu Chun (Mr))
Subject: Looking for Ph.D and PostD. on Dynamic Fracture.
Organization: National University of Singapore
X-Newsreader: Tin 1.1 PL4
Date: Thu, 19 Nov 1992 03:08:00 GMT

If you are interested in my friend, please email me.
engp1058@nuscc.nus.sg or engp2043@nusvm.bitnet

Lu Chun  

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                  Personal Biographical Notes
 
     My name is Wang Zeping(Z. P. Wang), male and thirty-five
years old. My experience is as following;
     Form March of 1978 to January of 1982, studied in Geophysics
Department at Beijing University and obtained Bachelor Degree of
Science.
     From February of 1982 to January of 1985, studied as a
master student in Survey Geophysics Institute of Chinese Academy
of Science and obtained Master Degree of Science.
     From February of 1985 to October of 1987, worked as a
lecturer in Changsha Institute of Technology.
     From December of 1987 to March of 1992, studied as a Ph.D
student in Beijing Institute of Technology and obtained Ph.D.
Meanwhile I were engaged as appraiser of National Science
Foundation of China.
     Form April of 1992 to now, working as a postdoctor in
Institute of Applied Mechanics at Southwest Jiaotong University.
     I am proficient in computer-calculation and theoretic
analysis, also familiar with experiments especially high velocity 
impact tests. A new model describing dynamic fracture in ductile
material has recently been presented by means of meso-damage
mechanics and conversation of energy. In the model an accurate
solutions to represent inertial effects and temperature effects
are given.
     The research I am working on includes nonequilibrum
statistical theory of dynamic fracture, experiments of dynamic
materials such as superhard aluminum alloy, 45# steel and 40Cr
steel as well as simulations of processes of dynamic damage. To
carry on these research, other studies such as plastic wave
propagation, shock wave initiation and propagation in solid,
interaction between materials and constitutive relation under the
conditions of high and low loading rate are included.
     The courses I have learned are Mechanics, Heat, Electromagn-
etics, Optics, Atomics, Theoretical Mechanics, Thermodynamics and
Statistical Physics, Electrodynamics, Quantum-mechanics,
Elasticity, Plasticity, Elastoplastic Fracture Mechanics,
Explosive Mechanics, Stresses Waves, Shock waves Physics,
Mathematical Analysis, Linear Algebra, Mathematical and Physical
Methods, Possibility and Statistics, Real Variable Function,
Functional Analysis, Tensor Analysis, Computational Method,
Seismology, Terrestrial Magnetism, Terrestrial Electricity,
Gravity and Solid Tide.
     The subject of M.S. Thesis is "Study of Elastic Earth Model
in Theory, Numerical Simulation and Seismology Triggered by Tide
Stresses".
     The subject of Ph.D thesis is " Studies of Dynamic Fracture
in Ductile Materials".
     Abstract of Ph.D thesis is
 
                           Abstract
     In this doctor thesis, the major studied of dynamic ductile 
damage. The following works have been done:
     1. A dynamic failure model in ductile solids under the
application of a mean tensile stress is developed. The proposed
model considers void nucleation and growth as parts of the
failure process under dynamic loading conditions. In the
evolution of porosity, work-hardening behaviour, rate-dependent
contribution and inertial effects are considered.
     Temperature effect, which is caused by plastic work due to
plastic strain in condition of high strain rate, takes play an
important part in the growth of microvoid in ductile materials.
This effect is taken into account in this thesis. In this work,
since plastic strain is larger than elsewhere, we consider
influence of temperature in matrix near void rather than
macroscopic average temperature. A differential equation that
temperature must satisfy is given here.
     The viscosity of material is important in the model
presented in the work. Relation of viscosity and temperature is
given in which viscosity decrease as temperature increase. Seaman
and Johnson take viscosity of material a smaller value than one
given by experiments. But we, using relation of viscosity and
temperature, can take experimental value, and numerical calcula-
tions show that comparison of calculations and the data is well.
     2. A simple model of dynamic fracture for brittle materials,
based on Perzyna's idea and Seaman's experimental results, is
developed. Numerical simulation of metal uranium spall process
in its impact tests are carried out with the model. Fair
agreement between the computation and experimental data is
obtained.
     3. Experiments of one and two dimensional spallation in LY12
aluminum and pure copper are performed. Measure responses for
spall fracture are obtained. Distributions of porosity along with
distance from impact interface in target are obtained by means
of the quantitative photomicrography. In sample of LY12 aluminum
alloy, it is found that microvoides begin to nucleate from the
split second-phase particles and cracks expand along with the
region in which second-phase particles exist. Various mechanisms
of void nucleate, growth and coalescence are observed.
     4. One or two dimensional Lagrangian finite difference
dynamic codes are complied. The codes can calculate interaction
of explosive and materials, high velocity impact test, penetra-
tion, dynamic ductile and brittle fracture. Two dimensional code
can treat J and K slide lines, local rezone etc.
     5. The dynamic damage model presented in the thesis is
incorporated in one and two dimensional hydrodynamic computer
codes, to simulate the spall processes of LY12 aluminum alloy and
pure copper. Numerical calculations give very good representation
of the data.
 
             Papers published and to be published
 
1. Wang Zeping and Yun Shourong, Numerical Calculations of
Spallation in Ductile Solids, Explosion and Waves, Vol.11 (1),
pp.20-25, 1991.
 
2. Wang Zeping, Huang Fenglei and Yun Shourong, A Model for
Numerical Calculations of Spallation in Brittle Solids, Chinese
Journal of High Pressure Physics, Vol. 5 (2), pp.90-97, 1991.
 
3. Wang Zeping, Xie Fang and Yun Shourong, Spallation Studies
with Calculation, Journal of National Defence University of
Technology, Vol.13 (3), pp.24-31, 1991.
 
4. Wang Zeping, Huang Fenglei and Yun Shourong, Numerical
Simulation of Spallation in Ductile Solids, Journal De Physque
IV Vol.1, Octobre C3-573, 1991.
 
5. Wang Zeping, Huang Fenglei and Yun Shourong, Simulation of
Spallation in Brittle Solids, Acta Mechanica Solida Sinica(Engli-
sh-version), Vol.5 (1), pp.13-26, 1992.
 
6. Ze-Ping Wang and Min Hou, A Model of Dynamic Failure in
Ductile Materials, Acta Mechanica Solida Sinica (English-
version), Vol.5 (2), pp.193-202, 1992.
 
7. Wang Zeping, Zheng Jian, An Gang and Yun Shourong, A Dynamic
Ductile Failure Model, Explosion and Waves, Vol.12 (2), pp.136-
144, 1992.
 
8. Huang Fenglei, Wang Zeping, Yun Shourong and Ding Jing,
Numerical Simulation of Two-dimensional Spallation in Copper,
Proceedings of the International Symposium on Intense Dynamic
Loading and Its Effects, ChengDu, China, June 9-12, pp.324-326,
1992.
 
9. Wang Zeping, Yun Shourong, Lu Chun and Hou Min, Inertial
Effects on Growth of Void in Ductile Solids, Proceedings of the
International Symposium on Intense Dynamic Loading and Its
Effects, ChengDu, China, June 9-12, pp.278-281, 1992.
 
10. Wang Zeping, Hunag Fenglei and Yun Shourong, Study of One-
dimensional Dynamic Fracture in Ductile Materials, Journal of
Beijing Institute of Technology, Vol.12 (2), pp.9-15, 1992.
 
11. Wang Zeping and Yun Shourong, Studies of Dynamic Fracture in
LY12 Aluminum, Acta Armamen Tarh, to be published.
 
12. Wang Zeping and Yun Shourong, Experimental Studies of Dynamic
Failure Micro-Mechanism in Ductile Material, Explosion and Waves,
to be published.
 
13. Wang Zeping, Huang Fenglei, Hou Min and Ding Jing, Studies
of Dynamic Damage Behaviour in LY12 Aluminum Alloy Under the
Condition of High Loading Rate, Chinese Journal of High Pressure
Physics, To be published.
 
14. Wang Zeping, et al.,Description of Two-dimensional Spallation
in Pure Copper, Theoretical and Applied Fracture Mechanics, to
be published.
 
15. Wang Zeping et al,. Inertial Effects on Growth of Void in
Ductile Solids, Int. J. Impact Engng., to be published.
 
16. Wang Zeping and Huan Shi, Study of Two-dimensional Spallation
in Ductile Materials, Asia-Pacific Symposium on Advances in
Engineering Plasticity and Its Application, 14-17 December 1992,
Hong Kong.