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Following are some publications with reference to the use of ADINA. The pages give the Abstracts of some papers published since 1986 referring to ADINA. The most recent papers are listed first. All these papers may be searched using the box:
Seismic
response of cement-soil mixing pile composite foundation with
time-history analysis
Yang,
Zhi-Hua (Institute of Geotechnical Engineering, Dalian University of
Technology); Yang, Qing; Kong, Gang-Qiang; Luan, Mao-Tian Source:
Yantu Lixue/Rock and Soil Mechanics, v 29, n 3, March, 2008, p
805-810 Language: Chinese
ISSN:
1000-7598
Publisher:
Academia Sinica
Abstract:
The cement-soil mixing pile composite foundations are getting more
and more application to construction engineering. However, the
research on their response under dynamic loading, especially under
earthquake loading, is quite limited. Now, the seismic response
analysis in the time domain is performed with ADINA program,
considering the interactions among soil, foundation and the
superstructure. Based on these analyses, some conclusions which may
be useful for a seismic design of this type composite foundations are
drawn. (15 refs.) Keywords: Foundations -
Cements - Constitutive models - Earthquake
resistance - Finite element method - Mathematical
models - Seismic response - Soil
mechanics Secondary Keywords: Cement soil mixing pile
- Composite foundation - Earthquake load -
Dynamic interaction - Time history analysis -
ADINA - Construction engineering
Earthquake
response properties of the support structure of large cross section
tunnel
Jin,
Xiao-Guang (College of Civil Engineering, Chongqing University);
Zhang, Yong-Xing Source: Chongqing Jianzhu Daxue Xuebao/Journal of
Chongqing Jianzhu University, v 30, n 1, February, 2008, p 44-48
Language: Chinese
ISSN:
1006-7329 CODEN: CJGXEK
Publisher:
China National Publication Industry Trading Corporation
Abstract:
The response properties of displacement and stress of tunnel support
structure are discussed in detail under the action of horizontal
earthquake acceleration (Ya), longitudinal earthquake acceleration
(Za) and horizontal-longitudinal earthquake acceleration (YZa). This
discussion is based on an analysis of the surrounding rock -support
structure-earthquake interaction, adoption of an ADINA nonlinear
finite element and construction mechanics, and transient dynamic time
domain analysis of a large cross section tunnel. Results of analysis
show that: (1) Horizontal earthquake acceleration has important
influence on horizontal displacement, maximum principal stress,
acceleration and velocity. (2) Longitudinal earthquake acceleration
has important influence on longitudinal displacement, effective
stress, maximum and minimum principal stress, maximum shear stress,
acceleration and velocity. (3) When Ya=0.191 g and 0.440 g or
Za=0.141 g and their combined action, the initial support of tunnel
would be damaged and the local lining would have partial damage. (4)
When Ya-0.440 g or Za=0.326 g and their combined action, the lining
of tunnel would be damaged. (5) When Ya=0.880 g or 1 Za=0.652 g, the
support structure of tunnel would have severe damage. (8 refs.)
Study
on inner force and dislocation of segments caused by shield machine
attitude
Mo,
H.H. (Department of Civil Engineering, South China University of
Technology); Chen, J.S. Source: Tunnelling and Underground Space
Technology, v 23, n 3, May, 2008, p 281-291
ISSN:
0886-7798
Publisher:
Elsevier Ltd
Abstract:
Attitude deflection of shield machine is inevitable in process of
driving forward, therefore, the tail brush, circular shape retainer
and even shell of shield machine will extrude the exterior surfaces
of segments. The squeezing action acting on segments causes
dislocation, stress concentration and even crack in segments. Finite
element code, ADINA, was used to analyze numerical tunnel model of 9
segment rings. The loads acting on different segment rings included
squeezing action of tail brush under four attitude deflection,
jacking forces, grouting pressure and earth pressure. The aspects of
analysis included displacement feature and stress distribution. The
analysis results indicate attitude deflection of shield machine
causes biggish dislocation between segments, and the key segment is
the most affected and weakest part in same ring which causes
irregular displacement and dislocation in whole tunnel structure. In
general, under squeezing action induced by shield machine,
circumferential seam is much more affected than longitudinal seam.
The squeezing action causes the segment dislocation exceed the
limiting dislocation value which means curved bolt has extruded bolt
hole and crack or breakage frequently concentrates in key segment and
adjacent segment. Deflection of shield machine attitude is
inevitable, but two deflection attitudes, including shield machine
attitude deviates right direction and the head of shield machine goes
down, should be avoided. © 2007 Elsevier Ltd. All rights
reserved. (11 refs.) Keywords: Tunneling
machines - Cracks - Deflection (structures)
- Finite element method - Mathematical models
- Pressure effects - Stress concentration -
Structural loads - Tunnels
Secondary Keywords: Shield machine attitude - Shield
tunnel - Attitude deflection - Inner
force
A
finite element formulation based on non-associated plasticity for
sheet metal forming
Cvitanic,
Vedrana (Department of Mechanical Engineering and Naval Architecture,
Faculty of Electrical Engineering, Mechanical Engineering and Naval
Architecture); Vlak, Frane; Lozina, Zeljan Source: International
Journal of Plasticity, v 24, n 4, April, 2008, p 646-687
ISSN:
0749-6419 CODEN: IJPLER
Publisher:
Elsevier Ltd
Abstract:
In the present paper, a finite element formulation based on
non-associated plasticity is developed. In the constitutive
formulation, isotropic hardening is assumed and an evolution equation
for the hardening parameter consistent with the principle of plastic
work equivalence is introduced. The yield function and plastic
potential function are considered as two different functions with
functional form as the yield function of Hill [Hill, R., 1948. Theory
of yielding and plastic flow of anisotropic metals. Proc. Roy. Soc. A
193, 281-297] or Karafillis-Boyce associated model [Karafillis, A.P.
Boyce, M., 1993. A general anisotropic yield criterion using bounds
and a transformation weighting tensor. J. Mech. Phys. Solids 41,
1859-1886]. Algorithmic formulations of constitutive models that
utilize associated or non-associated flow rule coupled with Hill or
Karafillis-Boyce stress functions are derived by application of
implicit return mapping procedure. Capabilities in predicting planar
anisotropy of the Hill and Karafillis-Boyce stress functions are
investigated considering material data of Al2008-T4 and Al2090-T3
sheet samples. The accuracy of the derived stress integration
procedures is investigated by calculating iso-error maps. The updated
Lagrangian formulation of CBR shell element [Yoon, J.W., Yang, D.Y.,
Chung, K., 1999. Elasto-plastic finite element method based on
incremental deformation theory and continuum based shell elements for
planar anisotropic sheet materials. Comp. Meth. Appl. Mech. Eng. 174,
23-56] coupled with the developed constitutive formulations is
implemented into the finite element program ADINA 8.1 (2003) via user
defined subroutine CUSERG. The results of the cylindrical cup drawing
for Al2008-T4 and Al2090-T3 sheet samples are evaluated by comparison
with experimental data and predictions of Barlat [Barlat, F. et al.,
1997b. Yield function development for aluminum alloy sheets. J. Mech.
Phys. Solids 45, 1727-1763] associated model. © 2007
Elsevier Ltd. All rights reserved. (54 refs.)
Keywords: Sheet metal - Algorithms -
Aluminum alloys - Finite element method -
Plasticity Secondary Keywords: Anisotropic materials
- Constitutive behavior
An Evaluation and Comparison of Models for Maximum Deflection of Stiffened Plates Using Finite Element Analysis
Banai, Lior (School of Mechanical Engineering, Tel Aviv University); Pedatzur, Omri. Source: Marine Technology, Vol. 44, No. 4, October 2007, pp. 212–225
ISSN: 0025-3316 (print); 1542-0566 (online)
Publisher: Society of Naval Architects and Marine Engineers
Abstract: Stiffened plates form the backbone of most of a ship’s structure. Today, finite element (FE) models are used to analyze the behavior of such structural elements for different types of loads. In the past, when usage of computers and FE models were not used very much, analytical analysis methods were required. Two well-known methods have been developed for analyses of stiffened plates under lateral loading (uniform pressure), based on two different models, namely, the orthotropic plate model and the grillage model. Both models can give estimations for the maximum plate deflection under uniform lateral pressure. The objective of this paper is to present the two methods, evaluate and compare the methods using the finite element method, and finally implement the methods as a computer program for quick estimations of the maximum deflection of stiffened plates. The degree of accuracy of the two methods when compared to FE is discussed in some detail.
Keywords: Stiffened plate - maximum deflection - lateral pressure - H. A. Schade - orthotropic model - grillage model
Secondary Keywords: finite element model - computer program - estimation - stiffener - ADINA
Study
on material composition functions of gradient aluminum matrix
composite piston reinforced by ceramic fibers
Wang,
Su (Department of Automotive Engineering, Beijing University of
Aeronautics and Astronautics); Ni, Chun-Yang; Zhu, Yu-Ming; Zhu,
Xin-Xiong Source: Hangkong Xuebao/Acta Aeronautica et Astronautica
Sinica, v 28, n 1, January, 2007, p 234-239 Language: Chinese
ISSN:
1000-6893 CODEN: HAXUDJ
Publisher:
AAAS Press of Chinese Society of Aeronautics and Astronautics
Abstract:
Functionally gradient material components have better physical and
chemical properties than homogeneous material components. Because of
material distributing complexity and insufficient study on
functionally gradient material, there are lots of difficulties in
analysis of functionally gradient material components. Theory of
thermal properties of composites and finite element analysis software
ADINA are used to analyze the temperature field and stress field of
gradient aluminum matrix composite piston reinforced by ceramic
fibers which have different material composition functions. The
result indicates that using gradient aluminum matrix composite layer
reinforced by ceramic fibers can remarkably change the temperature
distribution over the piston and relax the stresses at the interface
between the gradient aluminum matrix composite layer reinforced by
ceramic fibers and the noumenon of piston which is caused by mismatch
among different thermal expansion coefficients. Based on the
computing results, the curves of thermal peak value vs gradient
function coefficient, entire stress peak value vs gradient function
coefficient, and stress peak value between layers vs gradient
function coefficient can be fitted and proved by computing other
pistons. (8 refs.) Keywords: Pistons -
Ceramic fibers - Chemical properties -
Computer simulation - Finite element method -
Functionally graded materials - Stress
concentration - Temperature distribution - Thermal
expansion - Thermodynamic properties
Secondary Keywords: Functionally gradient material components -
Temperature field - Stress field
Analysis
of traffic flow based on the finite element method
Cui,
Jian-Ming (College of Traffic and Transportation, Southwest Jiaotong
University, Box 356); Ye, Huai-Zhen Source: International Conference
on Transportation Engineering 2007, ICTE 2007, International
Conference on Transportation Engineering 2007, ICTE 2007, 2007, p
94-99
Conference:
International Conference on Transportation Engineering 2007, ICTE
2007, Jul 22-24 2007, Chengdu, China
Publisher:
American Society of Civil Engineers
Abstract:
Analysis of normal traffic flow usually uses the static or dynamic
model based on fluid mechanics. However, in the analysis process, the
problem of massive modeling and data handling exists, and the
accuracy is desirable. Finite element method has been widely applied
in various domains. Based on existing theory of traffic flow, ITS and
the development of finite element, the paper presents a simulation
method based on finite element for solving problems in traffic flow.
Using existing finite element analysis software, the traffic flow is
simulated and analyzed with fluid mechanics and dynamics. The problem
with massive data processing through manual modeling and Numerical
Analysis is solved. Finally, a typical case of special road is
analyzed with ADINA finite element analysis software. Copyright ASCE
2007. (8 refs.) Keywords: Traffic control
- Computer simulation - Computer software -
Data handling - Dynamic models - Finite
element method - Problem solving - Static
analysis Secondary Keywords: Traffic flow - Massive
modelings - ADINA
An
adhesion process for space solar cells
Zhao,
H. (The Robotics Institute, School of Mechanical Engineering,
Shanghai Jiao Tong University); Fu, Z.; Li, P.B.; Zhao, Y.Z. Source:
Journal of Adhesion, v 83, n 12, December, 2007, p 1003-1029
ISSN:
0021-8464 CODEN: JADNAJ
Publisher:
Taylor and Francis Inc.
Abstract:
A type of silicone adhesive was used for bonding anti-irradiation
cover glasses to space solar cells. A new adhesion process for solar
cells was designed, and implemented by means of an automated coating
and bonding system based on an industrial robot. On the basis of
non-Newtonian fluid theory, flow models of three sub-processes were
created, and the commercial finite element analysis code Adina was
employed to simulate the whole process. The purpose of the
investigation was to acknowledge the mechanism of the adhesion
process and identify correlative factors that influence the adhesion
quality, to provide a basis for optimization of the adhesion process.
A simulation platform was created, to make it possible to evaluate or
predict the adhesion quality of space solar cells when the dimensions
of the solar cells and the adhesive were changed. (59 refs.)
Keywords: Solar cells - Adhesion
- Bonding - Coatings - Computer
simulation - Dynamic mechanical analysis - Finite
element method - Industrial robots - Optimization
- Silicones Secondary Keywords: Anti-irradiation
cover - Correlative factors - Adhesion
process - Adhesion quality
Studying
on two yield-surface rheological model of frozen soil by unloading
state
Li,
Dong-Wei (Department of Civil Engineering, Anhui University of
Science and Technology); Wang, Ren-He; Hu, Pu; Cui, Hao Source: Yantu
Lixue/Rock and Soil Mechanics, v 28, n 11, November, 2007, p
2337-2342 Language: Chinese
ISSN:
1000-7598
Publisher:
Academia Sinica
Abstract:
The results of triaxial creep experiments for unloading state show
that the frozen soil has an obvious dilatancy, and its volume strain
should not be neglected. To fully reflect creep deformation laws of
frozen soil under unloading state, a rheological constitutive dynamic
model of frozen soil submitting to ellipse-DP two-yield-surface is
put forward by using Nishihara model as the basic element. And the
model is embedded in ADINA finite element program on the base of
secondary developing technique for finite element program. The
results of numerical simulation for triaxial creep experiments show
that the constitutive dynamic model of ellipse-DP two-yield-surface
can reflect some deformation properties of dilatancy and volume
strain of frozen soil very well; and it can coincide with the
experimental data, which can provide references for frozen projects
calculation. (14 refs.) Keywords: Frozen soils
- Constitutive models - Creep - Deformation
- Dynamic models - Finite element method -
Rheology - Strain Secondary Keywords: Two
yield surface model - Dilatancy - Volume
strain - Numerical simulation - Creep
deformation laws - ADINA finite element
program
Studies
on deformation mechanism and rock mass stability of high slopes of
Geheyan Power Station under multiple factors
Li,
Jian-Lin (College of Civil and Hydropower Engineering, China Three
Gorges University); Liu, Jie; Wang, Le-Hua Source: Yantu Gongcheng
Xuebao/Chinese Journal of Geotechnical Engineering, v 29, n 9,
September, 2007, p 1289-1295 Language: Chinese
ISSN:
1000-4548 CODEN: YGXUEB
Publisher:
Chinese Society of Civil Engineering
Abstract:
Through the finite elemental program of ADINA, a three-dimensional
model of high slopes of Geheyan Power Station was established. Based
on the unloading rock mass theory, the primary situation, excavation
situation, unloading situation, reinforcement situation, sluice
situation and creeping situation were considered. On the basis of the
stress analysis and deformation analysis, the deformation theory and
the stability of rock mass of the high slopes of Geheyan Power
Station under the condition of several factors were studied. And then
the function on distortion of the slopes were found. Compared with
the monitoring results, the validity of analysis was proved, and
further deformation of the high slopes was predicted. Meanwhile, some
suggestions for the monitoring disposal based on the analytical
results were given. (8 refs.) Keywords: Slope
stability - Computer simulation - Creep
- Deformation - Excavation - Finite
element method - Hydroelectric power plants - Rock
mechanics - Stress analysis Secondary Keywords: Three
dimensional model - Unloading rock mass theory -
Deformation mechanism - ADINA - Geheyan
power station - Primary situation - Excavation
situation - Unloading situation - Reinforcement
situation - Sluice situation - Creeping
situation - Deformation analysis - Validity
of analysis
Research
on parabolic yield-surface creep constitutive model of artificial
frozen soil
Li,
Dong-Wei (Department of Civil Engineering, Anhui University of
Science and Technology); Wang, Ren-He; Zhao, Yan-Hui; Hu, Pu Source:
Yantu Lixue/Rock and Soil Mechanics, v 28, n 9, September, 2007, p
1943-1948 Language: Chinese
ISSN:
1000-7598
Publisher:
Academia Sinica
Abstract:
The triaxial creep experiment of artificial frozen soil in deep
alluvium is performed by using self-developed a W3Z-200 apparatus of
triaxial creep frozen soil. Analyzing the experiment results,
applying parabolic yield criterion for improved viscoplasticity in
the Nishihara model and coupling degree of temperature, a new creep
constitutive model is established for describing frozen-soil's creep
characteristics under the complicated stress state. The model is
embedded in nonlinear ADINA finite element program in order to
numerically analyze easily. Numerical simulation of the shaft well
excavation process and field measurements of deformation of deep soil
frozen wall are performed in Huainan Mine; and the results show that
the established parabolic yield-surface constitutive model is correct
and reasonable for FEM numerical simulation of deep soil frozen wall.
(19 refs.) Keywords: Creep testing -
Computer simulation - Constitutive models -
Deformation - Excavation - Finite
element method - Frozen soils - Temperature
- Viscoplasticity Secondary Keywords: Complex stress
condition - Triaxial compressive creep - Parabolic
yield surface - Artificial frozen soil - Triaxial
creep experiment - Alluvium - W3Z 200
apparatus - Nishihara model - Coupling
degree - ADINA - Numerical simulation -
Shaft well
Numerical
solution of elastic bodies in contact by FEM utilising equilibrium
displacement fields
Frastia,
Lubor (Department of Applied Mechanics, SjF, ZU) Source:
Computational Mechanics, v 41, n 1, December, 2007, p 159-174
ISSN:
0178-7675 CODEN: CMMEEE
Publisher:
Springer Verlag
Abstract:
In this paper a new effective formulation of the computation of the
statics of elastic bodies in contact is described and demonstrated.
Line contact, plane strain, and negligible friction are assumed. The
formulation is an extension of the standard finite element method
(FEM). With the aim to utilise the Hertz theory directly, we use the
exact solution of the elastic 2-dimensional halfspace loaded by
Hertzian pressure distribution and enforce the contact condition by
the method of Lagrange multipliers. In numerical examples we have
focussed on the demonstration and evaluation of the accuracy of the
new formulation for selected applications compared with the state of
the art node-to-segment contact algorithm implemented in the software
system ADINA. Proposed formulation is more accurate for problems
where Hertz contact dominates the strain state, especially for small
number of elements, whereas we obtained a fairly good agreement with
ADINA for a more general bending problem. © 2007 Springer
Verlag. (17 refs.) Keywords: Elasticity -
Finite element method - Friction - Lagrange
multipliers - Numerical methods - Pressure
distribution - Static analysis -
Strain Secondary Keywords: Variational methods
- Elastic bodies - Hertz theory
Improvement
of local mechanical properties of concrete segment by steel-fiber
reinforcement
Mo,
Hai-Hong (School of Architecture and Civil Engineering, South China
Univ. of Tech.); Chen, Jun-Sheng; Liang, Song; Yang, Yi-Bo; Su, Yi
Source: Huanan Ligong Daxue Xuebao/Journal of South China University
of Technology (Natural Science), v 35, n 7, July, 2007, p 116-121
Language: Chinese
ISSN:
1000-565X CODEN: HLDKEZ
Publisher:
South China University of Technology
Abstract:
In order to reveal the effect of steel-fiber reinforcement on the
local mechanical properties of concrete segments used in shield
tunnels, a general 3D finite element code, ADINA, was used to
numerically analyze the cracking loads, stress distributions and
crack distributions of the steel fiber-reinforced concrete (SFRC)
segment under the jacking force or in a regular service stage. The
results indicate that the addition of steel fibers can effectively
improve the local mechanical properties of segment surface, hand
holes and bolt holes, greatly enhance the anti-crack performance of
SFRC segment, and make the first-crack load 13.3%-22.7% greater than
that of the original reinforced concrete segment. (10 refs.)
Keywords: Fiber reinforced materials -
Cracking (chemical) - Reinforced concrete -
Reinforcement Secondary Keywords: Steel fiber -
Shield tunnel - Segment - Mechanical
property
Simulation
of hot rolling of magnesium strip by using finite element technique
Shen,
G. (Materials Technology Laboratory, CANMET); Essadiqi, E.; Galvani,
C.; Spencer, K.; Elwazri, A.; Yue, S. Source: Magnesium Technology,
Magnesium Technology 2007 - Proceedings of Symposium Sponsored by the
Magnesium Committee of the Light Metals Division of TMS, 2007, p
59-68
ISSN:
1545-4150 ISBN-10: 0873396634
Conference:
TMS 2007 Annual Meeting and Exhibition, Feb 25-Mar 1 2007, Orlando,
FL, United States
Publisher:
Minerals, Metals and Materials Society
Abstract:
Finite element thermal and mechanical models were developed to
simulate the thermal and mechanical behaviour of magnesium strip
during hot rolling. The commercial finite element software ADINA-TMC
was applied to couple the mechanical and thermal components
iteratively. A number of processes important rolling parameters such
as the roll speed, the dynamic contact between the roll and the
strip, deformation-induced heating, friction on the contact surfaces,
heat transfer both inside and between the strip and the roll have
been simulated. The temperatures and stresses of the magnesium strips
and the load applied on the strip for different rolling schedules
were predicted. Comparisons of the predicted and experimental exit
temperatures have been conducted for the magnesium alloy AZ31 for
different combinations of rolling temperatures, reductions and
rolling speeds. The difference between the predicted and measured
exit temperatures is less than 3% in most situations. The predicted
and measured values of load applied on the magnesium strip agree
reasonably for 14 passes conducted with two different rolling speeds.
The numerical model is used as a basis to discuss some important
issues in hot rolling, such as the contribution of plastic work to
the temperature change, effect of reduction rate on the effective
heat transfer coefficient between the strip and roll, and the
presence of residual stresses. (7 refs.) Keywords: Strip
metal - Deformation - Finite element method
- Friction - Hot rolling - Magnesium
alloys - Residual stresses Secondary Keywords: Magnesium
strips - Rolling speeds - Temperature
change
Restoring-force
test of fiber-reinforced plasterboard with concrete core column
Jiang,
Xin-Liang (School of Civil Engineering, Tianjin University); Gu, Yan
Source: Tianjin Daxue Xuebao (Ziran Kexue yu Gongcheng Jishu
Ban)/Journal of Tianjin University Science and Technology, v 40, n 5,
May, 2007, p 542-547 Language: Chinese
ISSN:
0493-2137 CODEN: TCHHA9
Publisher:
Tianjin University
Abstract:
The restoring-force test of two fiber-reinforced plasterboards
filled with concrete under horizontal cycle loading were carried out.
Based on the experiments, the behavior of the damage state, the
capacity of distortion and the ductility features were investigated.
Testing results indicate that the concrete core and fiber-reinforced
plasterboard work together to resist load effects, the earthquake
energy is dissipated by the plasterboard cracking, and the seismic
behavior and displacement ductility are increased. By using the
finite element analysis program ADINA, the calculation model was set
up to analyze the behavior of concrete core, fiber-reinforced
plasterboard and the composite wall respectively. The results
calculated by FEM are coincident with the testing ones, indicating
that the FEM model is appropriate for this case. (8 refs.)
Keywords: Columns (structural) - Composite
materials - Ductility - Failure (mechanical)
- Fiber reinforced materials - Finite element
method - Loading - Strain
measurement Secondary Keywords: Fiber-reinforced
plasterboard - Restoring force test - Damage
feature - Distortion capacity
Using
of laser ablation to fabrication nanocrystalline multilayer coatings
for biomedical and tribological application
Major,
Boguslaw (Institute of Metallurgy and Materials Science, Polish
Academy of Sciences); Major, Roman; Lackner, Jurgen M.; Waldhauser,
Wolfgang Source: Proceedings of SPIE - The International Society for
Optical Engineering, v 6598, Laser Technology VIII: Applications of
Lasers, 2007, p 659807
ISSN:
0277-786X CODEN: PSISDG
Conference:
Laser Technology VIII: Applications of Lasers, Sep 25-29 2006,
Szczecin-Swinoujscie, Poland Sponsor: SPIE Poland;Found. for the
Dev. of the Szczecin Univ. of Technol., Poland
Publisher:
SPIE -International Society for Optical Engineering
Abstract:
Titanium nitride (TiN) is regarded as a potential biomaterial for
blood-contact applications. TiN thin films were fabricated by pulsed
laser deposition with the Nd:YAG laser on biologically applied
polyurethane. Transmission electron microscopy (TEM) study of 350 nm
thick films revealed columnar structure. Such films were observed to
be brittle. In order to improve the coatings elasticity, the
thickness was reduced to 50nm, which limited the deposition mechanism
operation to the early stage. A biological test showed that TiN
surface film produced on polyurethane is characterized by good
biocompatibility and decreased surface affinity for cell adhesion.
The physical explanation of TEM images was based on the performed
finite element calculations of the temperature and stress
distribution using the ADINA program. Boron nitride thin layers were
produced by means of the pulsed laser deposition technique from
hexagonal boron nitride target. Two types of laser i.e. Nd:YAG with
Q-switch as well as KrF coupled with RF generator were used.
Influence of deposition parameters on surface morphology, phase
composition as well as mechanical properties is discussed. There are
an increasing number of applications in tribology where the
properties of a single material are not sufficient. One way to
surmount this problem is to use a multilayer coating. Application of
metallic interlayers improves adhesion of nitride hard layer in
multilayer systems. Tribological coatings consisted of 4, 8 and 32
layers of Cr/CrN and Ti/TiN types were fabricated with the PLD
technique. It is found in transmission electron examinations on thin
foils prepared from cross-section that both nitride-based multilayer
structures studied are characterized by small columnar crystallite
sizes and high defect density, what might raise their hardness but
compromise coating adhesion. The intermediate metallic layers
contained larger sized and less defective columnar structure compared
to the nitride layers, which should improve the coatings toughness.
Switching from single layer to multi-layer metal/nitride composition
improved resistance to delamination. (43 refs.)
Keywords: Nanocrystalline materials - Biomedical
engineering - Laser ablation - Neodymium
lasers - Polyurethanes - Pulsed laser
deposition - Titanium nitride - Transmission
electron microscopy Secondary Keywords: Columnar structure
- Multilayer coatings - Tribological
coatings
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