Ciència dels Materials

Blocs Temàtics:

Tema 1. Materials d’enginyeria Tema 2. Enllaç Químic Tema 3. Estructura Cristal·lina perfecta Tema 4. Estructura Cristal·lina imperfecta. Defectes Tema 5. Diagrames de fases. Equilibri microestructural. Diagrames importants en materials d’enginyeria Tema 6. Equilibri i Cinètica. Tractament Tèrmic. Diagrames TTT Tema 7. Metalls. Alliatges ferris i no ferris. Propietats mecàniques. Tema 8. Ceràmics i vidres. Tema 9. Polímers i composites Tema 10. Degradació i falla dels materials.

Tema 1. Materials d’enginyeria

Materiales més de 162.000.000 d’entrades a Google en 2011, i més de 203.000.000 en 2012

Materials més de 1000.000.000 d’entrades en Google (2011), més de 1250.000.000 en 2012.

Evolució històrica de la tecnologia de materials

Eines i armes del neolític 17.000 anys aC

Art al neolític (Bisonte en Altamira; 13.000 a.C.

Òxids de ferro i carbó

Obtenció dels metalls: Edat del bronze (Cu/Sn) 3.000-800 anys a.C.

Òxids de ferro i carbó

Materials ceràmics i vidres: Desde l’antiguitat fins a la modernitat

Materials ceràmics i vidres: Des de l’antiguitat fins a la modernitat

1.- Fibra óptica 2.- Recubriment ajustat 3.- Reforç d’aramida 4.- Coberta

Materials ceràmics i vidres: Des de l’antiguitat fins a la modernitat

Materials ceràmics i vidres: Des de l’antiguitat fins a la modernitat

Nous materials

Fibra de carboni

ZYLON

Projecte ITER

Nanotecnologia Don Eigler (1989)

Nanotecnologia: Piles de combustible

Nous materials: Biomaterials

Classification of Materials

  Metals and Alloys   Ceramics, Glasses, and Glass-ceramics   Polymers (plastics)   Semiconductors   Composite Materials

Table 1.1 Representative examples, applications, and properties for each category

of materials

Example of Applications Properties

Metals and Alloys Gray cast iron Automobile engine blocks Castable, machinable,

vibration damping Ceramics and Glasses SiO2-Na2O-CaO Window glass Optically transparent,

thermally insulating Polymers Polyethylene Food packaging Easily formed into thin,

flexible, airtight film

Example of Applications Properties

Semiconductors Silicon Transistors and integrated Unique electrical

circuits behavior

Composites Carbide cutting tools for High hardness, yet Tungsten carbide machining good shock resistance -cobalt (WC-Co)

Table 1.1 Continued

Section 1.3 Functional Classification of Materials

  Aerospace   Biomedical   Electronic Materials   Energy Technology and Environmental Technology   Magnetic Materials   Photonic or Optical Materials   Smart Materials   Structural Materials

© 2003 B

rooks/Cole Publishing / Thom

son Learning™

Functional classification of materials. Notice that metals, plastics, and ceramics occur in different categories. A limited number of examples in each category is provided

Section 1.4 Classification of Materials-Based on Structure

  Crystalline material is a material comprised of one or many crystals. In each crystal, atoms or ions show a long-range periodic arrangement.   Single crystal is a crystalline material that is made of only one crystal (there are no grain boundaries).   Grains are the crystals in a polycrystalline material.   Polycrystalline material is a material comprised of many crystals (as opposed to a single-crystal material that has only one crystal).   Grain boundaries are regions between grains of a polycrystalline material.

Section 1.5 Environmental and Other Effects

Effects of following factors must be accounted for in design to ensure that components do not fail unexpectedly:

  Temperature   Corrosion   Fatigue   Strain Rate

Section 1.6 Materials Design and Selection

  Density is mass per unit volume of a material, usually expressed in units of g/cm3 or lb/in.3

  Strength-to-weight ratio is the strength of a material divided by its density; materials with a high strength-to-weight ratio are strong but lightweight.

© 2003 B

rooks/Cole Publishing / Thom

son Learning™

Representative strengths of various categories of materials

Metalls

Common objects that are made of ceramic materials: scissors, a china teacup, a building brick, a floor tile, and a glass vase.

Ceràmics i vidres

Polímers

Several common objects that are made of polymeric materials: plastic tableware (spoon, fork, and knife), billiard balls, a bicycle helmet, two dice, a lawn mower wheel (plastic hub and rubber tire), and a plastic milk carton.

Polímers

Materials compostos

Semiconductors

Microestructura i propietats

Selecció d’un material segons la seva aplicació