Alumina Reinforced High Porosity Al-alloys with Extreme Hardness Dr. László A. Gömze 1, University of Miskolc, Miskolc, Hungary Tel.: Zellulare Werkstoffe May May 10-11, 2011, Freiberg, Germany Ludmila N. Gömze 2, IGREX Engineering Service Ltd. Igrici, Hungary Tel.:

Our Aims develop 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 Zellulare Werkstoffe May May 10-11, 2011, Freiberg, Germany

develop save collisions hitsOn 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 v ≥ 1000 m/s. Develop light metal alloysDevelop 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 Zellulare Werkstoffe May May 10-11, 2011, Freiberg, Germany Our main research directions

Multiple values of Young’s modulusMultiple values of Young’s modulus High damage toleranceHigh damage tolerance Ability to absorb and dissipate the elastic energy during crack propagationAbility to absorb and dissipate the elastic energy during crack propagation Good thermal shock resistanceGood thermal shock resistance Alumina Reinforced High Porosity Al-alloys with Extreme Hardness Zellulare Werkstoffe May May 10-11, 2011, Freiberg, Germany Advantages of Hetero-Modulus Materials

Advantages of Hetero-Modulus and Hetero-Viscous Complex Materials High damage toleranceHigh damage tolerance Higher deformation toleranceHigher deformation tolerance Ability to absorb and dissipate the collision energyAbility to absorb and dissipate the collision energy Relax by time mechanical stress developed in body during high speed collisions.Relax by time mechanical stress developed in body during high speed collisions. Alumina Reinforced High Porosity Al-alloys with Extreme Hardness Zellulare Werkstoffe May May 10-11, 2011, Freiberg, Germany

Some Complex Materials Having Excellent Dynamic Strength Automobile tyres Asphalt mixtures Ceramics made from hetero-modulus and hetero-viscous particles Alumina Reinforced High Porosity Al-alloys with Extreme Hardness Zellulare Werkstoffe May May 10-11, 2011, Freiberg, Germany

Alumina Reinforced High Porosity Al-alloys with Extreme Hardness Zellulare Werkstoffe May 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.)Complex material has several Young’s modulus (E=var.) and viscosity (η=var.) Flying (hit) object has inhomogeneous density (ρ≠const.)Flying (hit) object has inhomogeneous density (ρ≠const.) ρ i : ρ i : density of the „i-th” component of flying object; [kg/m 3 ] A 1j A 2j : A 1j and A 2j : surface of fractures of „j-th” Young’s modulus component of hetero-modulus body [m 2 ] A 3j : surface of deformed „j-th” Young’s modulus component of hetero-modulus body [m 2 ] E j : E j : The Young’s modulus of the „j-th” component of hetero-modulus body ; [N/m 2 ] i=1, 2, …, n: i=1, 2, …, n: the number of different density components of flying object j=1, 2, …, n: j=1, 2, …, n: the number of different Young’s modulus components of hetero-modulus body l 1j l 2j : l 1j and l 2j : deep and „movement” of fractures of „j-th” Young’s modulus component of hetero-modulus body [m] l 3j : Size of deformation of „j-th” Young’s modulus component of hetero-modulus body [m] R P R Sj : R Pj and R Sj : the pressure and shear strength of „j-th” Young’s modulus component of hetero-modulus body [N/m 2 ] V i : V i : volume of „i-th” component of flying object [m 3 ] Alumina Reinforced High Porosity Al-alloys with Extreme Hardness Zellulare Werkstoffe May 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 Where: C 1 and C 2 : constants of integration Alumina Reinforced High Porosity Al-alloys with Extreme Hardness Zellulare Werkstoffe May May 10-11, 2011, Freiberg, Germany

multiple values of Young’s modulus therefore these composite materials have ability to absorb and dissipate the elastic energy during crack propagation.Having multiple values of Young’s modulus therefore these composite materials have ability to absorb and dissipate the elastic energy during crack propagation. better hardnessThanking to ceramic particles these material compositions have better hardness and wear resistancy. thermal conductivitiesthermal shock resistancesDue 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 Zellulare Werkstoffe May 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 Zellulare Werkstoffe May 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 Zellulare Werkstoffe May May 10-11, 2011, Freiberg, Germany Impregnation of the molten metal Pore Metal 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 Zellulare Werkstoffe May May 10-11, 2011, Freiberg, Germany SelectingSelecting the ceramic raw materials and pore forming additives Forming sinteringForming and sintering the high porosity Al 2 O 3 cellular ceramics FilteringFiltering the Al metal alloys into the Al 2 O 3 cellular ceramic matrix of the required shapes Tempering resinteringTempering and reactive resintering

Preparing high porosity Al 2 O 3 cellular ceramics Alumina Reinforced High Porosity Al-alloys with Extreme Hardness Zellulare Werkstoffe May May 10-11, 2011, Freiberg, Germany Al 2 O 3Selection of Al 2 O 3 powder. additivesSelection the raw material additives. Al 2 O 3 A,B,C,D,E,GPreparing the raw material (Al 2 O 3 ) and the pore forming additives (A,B,C,D,E,G) mix. Al 2 O 3 A,B,C,D,E,GShaping and forming the raw material (Al 2 O 3 ) and the pore forming additives (A,B,C,D,E,G) mix. Al 2 O 3 A,B,C,D,E,GSintering the formed raw material (Al 2 O 3 ) with the pore forming additives (A,B,C,D,E,G). Al 2 O 3 AlExamination the quality of the prepared Al 2 O 3 ceramics as matrix material for Al alloys.

Selection of Al 2 O 3 powders and pore forming additives Alumina Reinforced High Porosity Al-alloys with Extreme Hardness Zellulare Werkstoffe May May 10-11, 2011, Freiberg, Germany IIIIIIIV Al 2 O 3 (g)100 A (g)12 B (g)10 C (g)10 D (g)10 E (g)2.5 G (g)6666 Water (g)xxxx Distribution of the particle size of the alumina

Alumina Reinforced High Porosity Al-alloys with Extreme Hardness Zellulare Werkstoffe May May 10-11, 2011, Freiberg, Germany Shaping and forming specimens from the raw material (Al 2 O 3 ) 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 Zellulare Werkstoffe May May 10-11, 2011, Freiberg, Germany Sintering curve Al 2 O 3 A,B,C,D,E,G Sintering curve of the specimens from the formed raw material (Al 2 O 3 ) with the pore forming additives (A,B,C,D,E,G) Sintering the formed specimens 1 st step 2 nd step Natural Cooling 1 st step Heating rate: 50 ℃ /hour Heating temperature: 300 ℃ Keeping time: 2 hour Atmosphere: Air 2 nd step 1 st Heating rate: 50 ℃ /hour 2 nd Heating rate: 100 ℃ /hour Heating temperature: 1350 ℃ Keeping time: 5 hour Atmosphere: Air

Alumina Reinforced High Porosity Al-alloys with Extreme Hardness Zellulare Werkstoffe May May 10-11, 2011, Freiberg, Germany Modelling the pore-forming process during sintering Al 2 O 3 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 Zellulare Werkstoffe May May 10-11, 2011, Freiberg, Germany The achieved porosities of Al 2 O 3 cellular ceramic material for matrix

Alumina Reinforced High Porosity Al-alloys with Extreme Hardness Zellulare Werkstoffe May May 10-11, 2011, Freiberg, Germany The typical microstructures of the developed Al 2 O 3 cellular ceramic matrix material

Alumina Reinforced High Porosity Al-alloys with Extreme Hardness Zellulare Werkstoffe May May 10-11, 2011, Freiberg, Germany Filtering the Al metal alloys into the Al 2 O 3 cellular ceramics Argon gas Al-alloy Cellular Al 2 O 3

Alumina Reinforced High Porosity Al-alloys with Extreme Hardness Zellulare Werkstoffe May May 10-11, 2011, Freiberg, Germany Problems of wetting during filtering the Al metal alloys into the Al 2 O 3 cellular ceramics Materi al θ Molten metal Pressure less impregnation method Pore Contact angle P Pressure impregnation method

Alumina Reinforced High Porosity Al-alloys with Extreme Hardness Zellulare Werkstoffe May May 10-11, 2011, Freiberg, Germany Typical microstructures of the developed low density Al 2 O 3 reinforced high porosity Al alloys during not enough wetting Al-alloy Al 2 O 3

Fe, Mn Fe Al Si Alumina Reinforced High Porosity Al-alloys with Extreme Hardness Zellulare Werkstoffe May May 10-11, 2011, Freiberg, Germany Typical microstructures of the developed low density Al 2 O 3 reinforced high porosity Al alloys with extreme hardness

Alumina Reinforced High Porosity Al-alloys with Extreme Hardness Zellulare Werkstoffe May 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 Average1198 INSTRON Tukon 2100B hardness tester

Alumina Reinforced High Porosity Al-alloys with Extreme Hardness Zellulare Werkstoffe May May 10-11, 2011, Freiberg, GermanySummary successfully Al 2 O 3 Al-alloyThe authors successfully find at least one pore forming additive using which the wetting angle between Al 2 O 3 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 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/cm 3 and at 100 N loading force hardness higher than HV 1100.The developed by authors alumina reinforced high porosity Al-alloys have density less, than 1.3 g/cm 3 and at 100 N loading force hardness higher than HV 1100.

Acknowledgement 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 Zellulare Werkstoffe May May 10-11, 2011, Freiberg, Germany

Thank you very much for your time and kind attention ! László A. Gömze University of Miskolc 3515, Miskolc, Hungary Phone: Liudmila N. Gömze Igrex Ltd. 3459, Igrici, Hungary Phone: Alumina Reinforced High Porosity Al-alloys with Extreme Hardness Zellulare Werkstoffe May May 10-11, 2011, Freiberg, Germany