alumina reinforced high porosity al-alloys with extreme hardness
DESCRIPTION
Zellulare Werkstoffe May 10-11, 2011, Freiberg , Germany. Alumina Reinforced High Porosity Al-alloys with Extreme Hardness . Dr . László A. Gömze 1 , University of Miskolc , Miskolc, Hungary Tel .: +36 30 746 2714 1 femgomze@ uni-miskolc.hu. Ludmila N. Gömze 2 , - PowerPoint PPT PresentationTRANSCRIPT
Alumina Reinforced High Porosity Al-alloys with
Extreme Hardness
Dr. László A. Gömze1, University of Miskolc,
Miskolc, Hungary
Tel.: +36 30 746 [email protected]
Zellulare Werkstoffe May 10-11, 2011, Freiberg, Germany
Ludmila N. Gömze2, IGREX Engineering Service Ltd.
Igrici, Hungary
Tel.: +36 30 746 [email protected]
Our Aims
On the basis of industry requirements develop ceramic reinforced low density new material compositions with some extreme mechanical properties as:
• dynamic strength, • hardness, • wear resistance.
.
Alumina Reinforced High Porosity Al-alloys with Extreme Hardness [email protected] http://keramia.uni-miskolc.hu [email protected]
Zellulare Werkstoffe May 10-11, 2011, Freiberg, Germany
• On the basis of ceramic matrices develop hetero-modulus and hetero-viscous complex material systems to save transport and flying equipment from collisions and hits with metallic and other bodies at speeds of:
v ≥ 1000 m/s.
• Develop high porosity, low density hetero-modulus ceramic reinforced composites of light metal alloys with increased hardness and wear resistance.
Alumina Reinforced High Porosity Al-alloys with Extreme Hardness [email protected] http://keramia.uni-miskolc.hu [email protected]
Zellulare Werkstoffe May 10-11, 2011, Freiberg, Germany
Our main research directions
• Multiple values of Young’s modulus
• High damage tolerance
• Ability to absorb and dissipate the elastic energy during crack propagation
• Good thermal shock resistance
Alumina Reinforced High Porosity Al-alloys with Extreme Hardness [email protected] http://keramia.uni-miskolc.hu [email protected]
Zellulare Werkstoffe May 10-11, 2011, Freiberg, Germany
Advantages of Hetero-Modulus Materials
Advantages of Hetero-Modulus and Hetero-Viscous Complex Materials
• High damage tolerance• Higher deformation tolerance• Ability to absorb and
dissipate the collision energy• Relax by time mechanical
stress developed in body during high speed collisions.
Alumina Reinforced High Porosity Al-alloys with Extreme Hardness [email protected] http://keramia.uni-miskolc.hu [email protected]
Zellulare Werkstoffe May 10-11, 2011, Freiberg, Germany
Some Complex Materials Having Excellent Dynamic Strength
Automobile tyres Asphalt mixturesCeramics made from hetero-modulus and
hetero-viscous particles
Alumina Reinforced High Porosity Al-alloys with Extreme Hardness [email protected] http://keramia.uni-miskolc.hu [email protected]
Zellulare Werkstoffe May 10-11, 2011, Freiberg, Germany
Alumina Reinforced High Porosity Al-alloys with Extreme Hardness [email protected] http://keramia.uni-miskolc.hu [email protected]
Zellulare Werkstoffe May 10-11, 2011, Freiberg, Germany
Typical Destruction of Ceramic Composites Under High Speed (HS) Collisions (u≥1000 m/sec)
Typical destruction of ceramic composites (L=3 mm) during high speed collision
Typical destruction of ceramic composites (L=4 mm) during high speed collisions
The Energy Engorgement Through Fractures and Deformation of Hetero-Modulus and Hetero-Viscous Complex Materials during high speed
collision• Complex material has several Young’s modulus (E=var.) and viscosity (η=var.)• Flying (hit) object has inhomogeneous density (ρ≠const.)
ρi: density of the „i-th” component of flying object; [kg/m3]
A1j and A2j: surface of fractures of „j-th” Young’s modulus component of hetero-modulus body [m2]
A3j: surface of deformed „j-th” Young’s modulus component of hetero-modulus body [m2]Ej: The Young’s modulus of the „j-th” component of hetero-modulus body ; [N/m2]
i=1, 2, …, n: the number of different density components of flying objectj=1, 2, …, n: the number of different Young’s modulus components of hetero-modulus body l1j and l2j: deep and „movement” of fractures of „j-th” Young’s modulus component of hetero-modulus body [m]
l3j: Size of deformation of „j-th” Young’s modulus component of hetero-modulus body [m]RPj and RSj: the pressure and shear strength of „j-th” Young’s modulus component of hetero-modulus body [N/m2]
Vi: volume of „i-th” component of flying object [m3]
K
kkkk
M
jjjjspH
n
iii lAlAEWWWVu
144
133
1
2
2
Alumina Reinforced High Porosity Al-alloys with Extreme Hardness [email protected] http://keramia.uni-miskolc.hu [email protected]
Zellulare Werkstoffe May 10-11, 2011, Freiberg, Germany
The General Equation of Shear Stress Relaxation in Complex Hetero-Modulus and Hetero-Viscous Ceramics after High Speed
Collision
CDeCeC
tAC
AB
ABt
AC
AB
AB
2
2
2
2
422
421
Where:
C1 and C2: constants of integration
Alumina Reinforced High Porosity Al-alloys with Extreme Hardness [email protected] http://keramia.uni-miskolc.hu [email protected]
Zellulare Werkstoffe May 10-11, 2011, Freiberg, Germany
• Having multiple values of Young’s modulus therefore these composite materials have ability to absorb and dissipate the elastic energy during crack propagation.
• Thanking to ceramic particles these material compositions have better hardness and wear resistancy.
• Due to metallic parts these hetero-modulus composite materials have much higher thermal conductivities and better thermal shock resistances.
Alumina Reinforced High Porosity Al-alloys with Extreme Hardness [email protected] http://keramia.uni-miskolc.hu [email protected]
Zellulare Werkstoffe May 10-11, 2011, Freiberg, Germany
Advantages of Hetero-modulus Ceramic Reinforced Light Metal Alloys
Methods to increase mechanical properties
Alumina Reinforced High Porosity Al-alloys with Extreme Hardness [email protected] http://keramia.uni-miskolc.hu [email protected]
Zellulare Werkstoffe May 10-11, 2011, Freiberg, Germany
Short fiber reinforced complex
material
Particle reinforced complex material
Continous fiber reinforced complex
material
Some methods to prepare foams and composite materials
Alumina Reinforced High Porosity Al-alloys with Extreme Hardness [email protected] http://keramia.uni-miskolc.hu [email protected]
Zellulare Werkstoffe May 10-11, 2011, Freiberg, Germany
Impregnation of the molten
metal
PoreMetal
• There are several methods to produce foams, cellular materials and low density, high porosity composites.
The main technological steps used by authors
Alumina Reinforced High Porosity Al-alloys with Extreme Hardness [email protected] http://keramia.uni-miskolc.hu [email protected]
Zellulare Werkstoffe May 10-11, 2011, Freiberg, Germany
• Selecting the ceramic raw materials and pore forming additives
• Forming and sintering the high porosity Al2O3 cellular ceramics
• Filtering the Al metal alloys into the Al2O3 cellular ceramic matrix of the required shapes
• Tempering and reactive resintering
Preparing high porosity Al2O3 cellular ceramics
Alumina Reinforced High Porosity Al-alloys with Extreme Hardness [email protected] http://keramia.uni-miskolc.hu [email protected]
Zellulare Werkstoffe May 10-11, 2011, Freiberg, Germany
• Selection of Al2O3 powder.• Selection the raw material additives.• Preparing the raw material (Al2O3) and the pore forming additives
(A,B,C,D,E,G) mix.• Shaping and forming the raw material (Al2O3) and the pore forming
additives (A,B,C,D,E,G) mix.• Sintering the formed raw material (Al2O3) with the pore forming
additives (A,B,C,D,E,G).• Examination the quality of the prepared Al2O3 ceramics as matrix
material for Al alloys.
Selection of Al2O3 powders and pore forming additives
Alumina Reinforced High Porosity Al-alloys with Extreme Hardness [email protected] http://keramia.uni-miskolc.hu [email protected]
Zellulare Werkstoffe May 10-11, 2011, Freiberg, Germany
Part ic le D iam eter (µ m .)
Volum e %
0
10
20
30
0
10
20
30
40
50
60
70
80
90
100
1.0 10.0 100.0 1000.0
I II III IVAl2O3 (g) 100 100 100 100
A (g) 12 12 12 12B (g) 10C (g) 10D (g) 10E (g) 2.5G (g) 6 6 6 6Water
(g)x x x x
Distribution of the particle size of the alumina
Alumina Reinforced High Porosity Al-alloys with Extreme Hardness [email protected] http://keramia.uni-miskolc.hu [email protected]
Zellulare Werkstoffe May 10-11, 2011, Freiberg, Germany
• Shaping and forming specimens from the raw material (Al2O3) and the pore forming additives (A,B,C,D,E,G) mix:
Forming the prepared raw material mix with pore forming additives
Alumina Reinforced High Porosity Al-alloys with Extreme Hardness [email protected] http://keramia.uni-miskolc.hu [email protected]
Zellulare Werkstoffe May 10-11, 2011, Freiberg, Germany
• Sintering curve of the specimens from the formed raw material (Al2O3) with the pore forming additives (A,B,C,D,E,G)
Sintering the formed specimens
0 10 20 300
200
400
600
800
1000
1200
1400
Time, /hourtTe
mpe
ratu
re,
/℃
T
1st step
2nd step
Natural Cooling
1st step
Heating rate: 50 ℃/hour
Heating temperature: 300 ℃
Keeping time: 2 hour
Atmosphere: Air
2nd step
1st Heating rate: 50 ℃/hour
2nd Heating rate: 100 ℃/hour
Heating temperature: 1350 ℃
Keeping time: 5 hour
Atmosphere: Air
Alumina Reinforced High Porosity Al-alloys with Extreme Hardness [email protected] http://keramia.uni-miskolc.hu [email protected]
Zellulare Werkstoffe May 10-11, 2011, Freiberg, Germany
Modelling the pore-forming process during sintering Al2O3 cellular ceramics
Liquid
Gas (Vapor)
Gas
Gas (Vapor)
From “Liquid and Solid” to “Gas (Vapor)”
From “Solid” to “Liquid”
: Liquid (Material G, Water)
: Solid (Additive materials B, C, D)
: Solid (Additive material E)
Alumina Reinforced High Porosity Al-alloys with Extreme Hardness [email protected] http://keramia.uni-miskolc.hu [email protected]
Zellulare Werkstoffe May 10-11, 2011, Freiberg, Germany
The achieved porosities of Al2O3 cellular ceramic material for matrix
Porosity of Alumina
III
III
IV
I
IIIII
IVI II III
IV
46
48
50
52
54
56
58
Poro
sity P
/%Ave.Max.Min.
Alumina Reinforced High Porosity Al-alloys with Extreme Hardness [email protected] http://keramia.uni-miskolc.hu [email protected]
Zellulare Werkstoffe May 10-11, 2011, Freiberg, Germany
The typical microstructures of the developed Al2O3 cellular ceramic matrix material
Alumina Reinforced High Porosity Al-alloys with Extreme Hardness [email protected] http://keramia.uni-miskolc.hu [email protected]
Zellulare Werkstoffe May 10-11, 2011, Freiberg, Germany
Filtering the Al metal alloys into the Al2O3 cellular ceramics
Argon gas
Al-alloy
Cellular Al2O3
Alumina Reinforced High Porosity Al-alloys with Extreme Hardness [email protected] http://keramia.uni-miskolc.hu [email protected]
Zellulare Werkstoffe May 10-11, 2011, Freiberg, Germany
Problems of wetting during filtering the Al metal alloys into the Al2O3 cellular ceramics
Material
Material
θ
Molten metal
Pressure less impregnation
method
Pore
Contact angle
PPressure
impregnation method
Alumina Reinforced High Porosity Al-alloys with Extreme Hardness [email protected] http://keramia.uni-miskolc.hu [email protected]
Zellulare Werkstoffe May 10-11, 2011, Freiberg, Germany
Typical microstructures of the developed low density Al2O3 reinforced high porosity Al alloys during not enough wetting
Al-alloy
Al2O3
Fe, Mn
Fe, Mn Fe
Fe
Al
Si
Alumina Reinforced High Porosity Al-alloys with Extreme Hardness [email protected] http://keramia.uni-miskolc.hu [email protected]
Zellulare Werkstoffe May 10-11, 2011, Freiberg, Germany
Typical microstructures of the developed low density Al2O3 reinforced high porosity Al alloys with extreme hardness
Alumina Reinforced High Porosity Al-alloys with Extreme Hardness [email protected] http://keramia.uni-miskolc.hu [email protected]
Zellulare Werkstoffe May 10-11, 2011, Freiberg, Germany
Surface hardness of the developed high porosity hetero-modulus Al alloy composites
HV10 hardness values measured on samples
Number of measure
HV10 hardness
1 12572 11783 12884 11235 11106 1231
Average 1198INSTRON Tukon 2100B hardness tester
Alumina Reinforced High Porosity Al-alloys with Extreme Hardness [email protected] http://keramia.uni-miskolc.hu [email protected]
Zellulare Werkstoffe May 10-11, 2011, Freiberg, Germany
Summary
• The authors successfully find at least one pore forming additive using which the wetting angle between Al2O3 matrix and Al-alloy could have considerably decreased.
• The developed new, cellular ceramics reinforced, low density Al-alloy composites have at least two, or more moduli of Young and have excellent ability to dissipate mechanical stresses.
• The developed by authors alumina reinforced high porosity Al-alloys have density less, than 1.3 g/cm3 and at 100 N loading force hardness higher than HV 1100.
Acknowledgement
The authors acknowledge to Igrex Engineering Service Ltd. for the financial and technical support of this research for several years and to young colleagues and PhD students of Department of Ceramic and Silicate Engineering at the University of Miskolc (Hungary) for laboratory tests and assistance.
Alumina Reinforced High Porosity Al-alloys with Extreme Hardness [email protected] http://keramia.uni-miskolc.hu [email protected]
Zellulare Werkstoffe May 10-11, 2011, Freiberg, Germany
Thank you very much for your time and kind attention !
http://keramia.uni-miskolc.hu http://www.szte.org.hu/folyoirat
László A. GömzeUniversity of Miskolc
3515, Miskolc, [email protected]
Phone: +36 30 7462714
Liudmila N. GömzeIgrex Ltd.
3459, Igrici, [email protected]
Phone: +36 30 7462713
Alumina Reinforced High Porosity Al-alloys with Extreme Hardness [email protected] http://keramia.uni-miskolc.hu [email protected]
Zellulare Werkstoffe May 10-11, 2011, Freiberg, Germany