ADVANCED MATERIALS. Prof. Stepan Mudry UNIVERSITY OF LVIV

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1 ADVANCED MATERIALS Prof. Stepan Mudry UNIVERSITY OF LVIV

2 Ivan Franko National University of Lviv.

3 Smoluchowski's scientific output included fundamental work on the kinetic theory of matter. In 1904 he was the first who noted the existence of density fluctuations in the gas phase and in 1908 he became the first physicist to ascribe the phenomenon of critical opalescence to large density fluctuations. His investigations also concerned the blue colour of the sky as a consequence of light dispersion on fluctuations in the atmosphere, as well as explanation of Brownian motion of particles. At that time Smoluchowski proposed formulae which presently carry his name. Marian Smoluchowski Lviv

4 Content -Classification of materials -Amorphous metallic alloys -Nanocrystalline materials -Composite materials -Magnetocaloric materials -Semi-solid metals -Shape memory alloys -Ferrofluids -Energetic materials

5 Why Materials??? Ashby,: Material Selection in Mechanical Design

6 Competition of materials Traditional materials - materials -weight reduction strategy; -corrosion resistance increase; -environment protection; -cost reduction; -new working capabilities - upgrade functions advanced

7 MATERIALS SCIENCE Physics Chemistry Mathematics Crystalline structure, chemical bonding, physical properties, thermodynamics, physical and chemical kinetics, surface phenomena, mathematical models, computer simulation methods, fractal geometry, statistical physics, electronic structure

8 Engineering Materials

9 Materials Ferrous metals: carbon-, alloy-, stainless-, tool-and-die steels Non-ferrous metals: aluminum, magnesium, copper, nickel, titanium, superalloys, refractory metals, beryllium, zirconium, low-melting alloys, gold, silver, platinum, Plastics: thermoplastics (acrylic, nylon, polyethylene, ABS, ) thermosets (epoxies, Polymides, Phenolics, ) elastomers (rubbers, silicones, polyurethanes, ) Ceramics, Glasses, Graphite, Diamond, Cubic Boron Nitride Composites: reinforced plastics, metal-, ceramic matrix composites Nanomaterials, shape-memory alloys, superconductors,

10 Properties of materials Mechanical properties of materials Strength, Toughness, Hardness, Ductility, Elasticity, Fatigue and Creep Physical properties Density, Specific heat, Melting and boiling point, Thermal expansion and conductivity, Electrical and magnetic properties Chemical properties Oxidation, Corrosion, Flammability, Toxicity,

11 Material Specification Chemical composition Mechanical properties Strength, hardness (under various conditions: temperature, humidity, pressure) Physical properties density, optical, electrical, magnetic Environmental green, recycling

12 Metals Ferrous Metals Cast irons Steels Super alloys Iron-based Nickel-based Cobalt-based Non-ferrous metals Aluminum and its alloys Copper and its alloys Magnesium and its alloys Nickel and its alloys Titanium and its alloys Zinc and its alloys Lead & Tin Refractory metals Precious metals

13 General Properties and Applications of Ferrous Alloys Ferrous alloys are useful metals in terms of mechanical, physical and chemical properties. Alloys contain iron as their base metal. Carbon steels are least expensive of all metals while stainless steels is costly.

14 Carbon steels Carbon and alloy steels Classified as low, medium and high: 1. Low-carbon steel or mild steel, < 0.3%C, bolts, nuts and sheet plates. 2. Medium-carbon steel, 0.3% ~ 0.6%C, machinery, automotive and agricultural equipment. 3. High-carbon steel, > 0.60% C, springs, cutlery, cable.

15 Alloy steels Carbon and alloy steels Steels containing significant amounts of alloying elements. Structural-grade alloy steels used for construction industries due to high strength. Other alloy steels are used for its strength, hardness, resistance to creep and fatigue, and toughness. It may heat treated to obtain the desired properties.

16 Carbon and alloy steels High-strength low-alloy steels Improved strength-to-weight ratio. Used in automobile bodies to reduce weight and in agricultural equipment. Some examples are: 1. Dual-phase steels 2. Micro alloyed steels 3. Nano-alloyed steels

17 Stainless steels Characterized by their corrosion resistance, high strength and ductility, and high chromium content. Stainless as a film of chromium oxide protects the metal from corrosion.

18 Stainless steels Five types of stainless steels: 1. Austenitic steels 2. Ferritic steels 3. Martensitic steels 4. Precipitation-hardening (PH) steels 5. Duplex-structure steels

19 Typical Selection of Carbon and Alloy Steels for Various Applications T A B L E 5.1 P ro d u ct S teel P ro d u ct S teel A ircraft fo rgin gs, tu b in g, fittin gs A u to m o b ile b o d ies A xles B all b earin gs an d races B o lts C am sh afts C h ain s (transm issio n ) C o il sp rin gs C o n n ectin g ro d s C ran kshafts (fo rged ) , , , 4042, , , , 3141, , 1145, , D ifferen tial gears G ears (car an d tru ck) L an d in g gear L o ck w ash ers N u ts R ailroad rails an d w h eels S p rin gs (co il) S p rin gs (leaf) T u b in g W ire W ire (m u sic) , , , , , , , , ,

20 Mechanical Properties of Selected Carbon and Alloy Steels in Various Conditions TABLE 5.2 Typical Mechanical Properties of Selected Carbon and Alloy Steels in the Hot-Rolled, Normalized, and Annealed Condition AISI Condition Ultimate tensile strength (MPa) Yield Strength (MPa) Elongation in 50 mm (%) Reduction of area (%) As-rolled Normalized Annealed As-rolled Normalized Annealed Normalized Annealed Normalized Annealed Normalized Annealed Hardness (HB)

21 AISI Designation for High-Strength Sheet Steel TABLE 5.3 Yield Strength psi x MPa Chemical Composition S = structural alloy X = low alloy W = weathering D = dual phase Deoxidation Practice F = killed plus sulfide inclusion control K = killed O = nonkilled

22 Room-Temperature Mechanical Properties and Applications of Annealed Stainless Steels TABLE 5.4 Room-Temperature Mechanical Properties and Typical Applications of Selected Annealed Stainless Steels Ultimate tensile Yield Elongation strength strength in 50 mm (MPa) (MPa) (%) Characteristics and typical applications AISI (UNS) 303 (S30300) 304 (S30400) 316 (S31600) Screw machine products, shafts, valves, bolts, bushings, and nuts; aircraft fittings; bolts; nuts; rivets; screws; studs Chemical and food processing equipment, brewing equipment, cryogenic vessels, gutters, downspouts, and flashings High corrosion resistance and high creep strength. Chemical and pulp handling equipment, photographic equipment, brandy vats, fertilizer parts, ketchup cooking kettles, and yeast tubs. 410 (S41000) 416 (S41600) Machine parts, pump shafts, bolts, bushings, coal chutes, cutlery, tackle, hardware, jet engine parts, mining machinery, rifle barrels, screws, and valves Aircraft fittings, bolts, nuts, fire extinguisher inserts, rivets, and screws.

23 Tool and die steels Designed for high strength, impact toughness, and wear resistance at a range of temperatures.

24 Basic Types of Tool and Die Steels TABLE 5.5 Type High speed Hot work Cold work Shock resisting Mold steels Special purpose Water hardening AISI M (molybdenum base) T (tungsten base) H1 to H19 (chromium base) H20 to H39 (tungsten base) H40 to H59 (molybdenum base) D (high carbon, high chromium) A (medium alloy, air hardening) O (oil hardening) S P1 to P19 (low carbon) P20 to P39 (others) L (low alloy) F (carbon-tungsten) W

25 Processing and Service Characteristics of Common Tool and Die Steels TABLE 5.6 Processing and Service Characteristics of Common Tool and Die Steels AISI designation Resistance to decarburization Resistance to cracking Approximate hardness (HRC) Machinability Toughness Resistance to softening Resistance to wear M2 Medium Medium Medium Low Very high Very high T1 High High Medium Low Very high Very high T5 Low Medium Medium Low Highest Very high H11, 12, 13 Medium Highest Medium to high Very high High Medium A2 Medium Highest Medium Medium High High A9 Medium Highest Medium High High Medium to high D2 Medium Highest Low Low High High to very high D3 Medium High Low Low High Very high H21 Medium High Medium High High Medium to high H26 Medium High Medium Medium Very high High P20 High High Medium to high High Low Low to medium P21 High Highest Medium Medium Medium Medium W1, W2 Highest Medium Highest High Low Low to medium Source: Adapted from Tool Steels, American Iron and Steel Institute, 1978.

26 What methods available to improve the properties of steel? Atomic structure----microscopic structure-----properties Traditional methods--thermal treatment, adding of special admixtures, plastic deformation New methods controlled solidification, laser irradiation, acoustic treatment etc.

27 Type of atomic structure crystalline quasicrystal amorphous fractal

28 Aluminium and aluminium alloys Factors for selecting are: 1. High strength to weight ratio 2. Resistance to corrosion 3. High thermal and electrical conductivity 4. Ease of machinability 5. Non-magnetic

29 Magnesium and magnesium alloys Magnesium (Mg) is the lightest metal. Alloys are used in structural and nonstructural applications. Typical uses of magnesium alloys are aircraft and missile components. Also has good vibration-damping characteristics.

30 Copper and copper alloys Copper alloys have electrical and mechanical properties, corrosion resistance, thermal conductivity and wear resistance. Applications are electronic components, springs and heat exchangers. Brass is an alloy of copper and zinc. Bronze is an alloy of copper and tin.

31 Nickel and nickel alloys Nickel (Ni) has strength, toughness, and corrosion resistance to metals. Used in stainless steels and nickel-base alloys. Alloys are used for high temperature applications, such as jet-engine components and rockets.

32 Superalloys Superalloys are high-temperature alloys use in jet engines, gas turbines and reciprocating engines.

33 Titanium and titanium alloys Titanium (Ti) is expensive, has high strengthto-weight ratio and corrosion resistance. Used as components for aircrafts, jet-engines, racing-cars and marine crafts.

34 Refractory metals Refractory metals have a high melting point and retain their strength at elevated temperatures. Applications are electronics, nuclear power and chemical industries. Molybdenum, columbium, tungsten, and tantalum are referred to as refractory metal.

35 Other nonferrous metals 1. Beryllium 2. Zirconium 3. Low-melting-point metals: - Lead - Zinc - Tin 4. Precious metals: - Gold - Silver - Platinum

36 Advanced materials 1. Shape-memory alloys (i.e. eyeglass frame, helical spring) 2. Amorphous alloys (Metallic Glass) 3. Nanomaterials 4. Metal foams 5. Magnetocaloric materias 6. Semi-solid metals 7. Multiferroics 8. Programmable materials

37 Annealing Heat Treatment of Metals Full annealing Normalising (faster rate of cooling) Recovery annealing (longer holding time, slower rate of cooling,) Stress relieving (lower temperature) Martensite formation in steel Austenitizing (conversion to austenite) Quenching (control cooling rate Tempering (reduce brittleness)

38 Heat Treatment of Metals Precipitation hardening Solution treatment (α-phase conversion) quenching precipitation treatment (aging) Surface hardening Carburizing Nitriding Carbonitriding Chromizing and Boronizing

39 Heat Treatment of Steel

40 Precipitation Hardening Solution treatment Quenching Precipitation treatment

41 Furnaces for Heat Treatment Fuel fire furnaces gas oil Electric furnaces batch furnaces box furnaces - door car-bottom furnaces - track for moving large parts bell-type furnaces - cover/bell lifted by gantry crane continuous furnaces

42 Furnaces for Heat Treatment Vacuum furnaces Salt-bath furnaces Fluidized-bed furnaces Some of the furnaces have special atmosphere requirements, such as carbon- and nitrogen- rich atmosphere.

43 Surface Hardening Methods Flame hardening Induction heating High-frequency resistance heating Electron beam heating Laser beam heating

44 Surface Hardening Methods Induction heating High frequency resistance heating

45 Classification of Ceramics Ceramics Traditional ceramics New ceramics Glass

46 Traditional ceramics Ceramics clays: kaolinite silica: quartz, sandstone alumina silicon carbide New ceramics oxide ceramics : alumina carbides : silicon carbide, titanium carbide, etc. nitrides : silicon nitride, boron nitiride, etc.

47 Glass Glass products window glass containers light bulb glass laboratory glass glass fibers optical glass Glass ceramics - polycrystalline structure

48 Classification of Polymers Thermoplastics Thermosets Elastomers

49 Polymers Thermoplastics - reversible in phase by heating and cooling. Solid phase at room temperature and liquid phase at elevated temperature. Thermosets - irreversible in phase by heating and cooling. Change to liquid phase when heated, then follow with an irreversible exothermic chemical reaction. Remain in solid phase subsequently. Elastomers - Rubbers

50 Thermoplastics Acetals Acrylics - PMMA Acrylonitrile-Butadiene-Styrene - ABS Cellulosics Fluoropolymers - PTFE, Teflon Polyamides (PA) - Nylons, Kevlar Polysters - PET Polyethylene (PE) - HDPE, LDPE Polypropylene (PP) Polystyrene (PS) Polyvinyl chloride (PVC)

51 Amino resins Epoxies Phenolics Polyesters Polyurethanes Silicones Thermosets

52 Elastomers Natural rubber Synthetic rubbers butadiene rubber butyl rubber chloroprene rubber ethylene-propylene rubber isoprene rubber nitrile rubber polyurethanes silicones styrene-butadiene rubber thermoplastic elastomers

53 Classification of Composite Materials Metal Matrix Composites Ceramic Matrix Composites Polymer Matrix Composites

54 Composite Materials Metal Matrix Composites (MMC) Mixture of ceramics and metals reinforced by strong, high-stiffness fibers Ceramic Matrix Composites (CMC) Ceramics such as aluminum oxide and silicon carbide embedded with fibers for improved properties, especially high temperature applications. Polymer Matrix Composites (PMC) Thermosets or thermoplastics mixed with fiber reinforcement or powder.

55 Composite Materials 1D fibre Woven fabric Random fibre

56 Composite Materials

57 Taxonomy of Materials Selection Ashby,: Material Selection in Mechanical Design

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