Materials Science: A Comprehensive Overview

Posted on Oct 23, 2024 in Geology

Materials Science

Introduction

Everything in the universe consists of matter, which occupies space and has mass. This matter presents itself in nature in various forms, each with specific properties. Matter is composed of atoms. The origin of these atoms can be traced back to the Big Bang (Hydrogen, Helium, and Lithium), the cores of stars (Iron), and supernova explosions (heavier atoms).

Classification of Materials

  • Raw Materials: Obtained directly from nature (e.g., wood, granite).
  • Processed Materials: Obtained by processing raw materials (e.g., panels, glass).
  • Synthetic Materials: Not found in nature, created through physical, technological, or chemical processes (e.g., plastics, fibers).
  • Recycled Materials: Obtained from objects made of the same material (e.g., glass, paper).

Properties of Use

Useful objects are made from the above materials, including metals and components for computers. Materials are chosen based on their specific properties.

Mechanical Properties

  • Hardness: Resistance to being scratched.
  • Toughness/Brittleness: Resistance to impact.
  • Malleability: Ability to be deformed into sheets.
  • Ductility: Ability to be deformed into wires.
  • Plasticity: Ability to deform easily under stress and retain the new shape.
  • Elasticity: Ability to deform easily under stress and return to the original shape when the stress is removed.
  • Mechanical Resistance: Resistance to compression, tension, torsion, bending, and shear.

Materials Throughout History

  • Stone Age: Use of rocks for tools.
  • Bronze Age: Use of bronze (copper + tin), enabled by mastery of fire.
  • Iron Age: Use of iron.
  • Age of New Metals: Exploration and utilization of a wider range of metals.

Metals

Properties

  • Conductors of Heat: Used in heat-transfer instruments.
  • Conductors of Electricity: Used in electrical machines.
  • Tough and Plastic: Used in construction.
  • Solid at Room Temperature: Used in packaging.
  • Oxidizable: Leads to various uses and technologies.

Classification of Metals

  • Ferrous Metals: Iron and its alloys (e.g., steel).
  • Non-Ferrous Metals: Heavy metals, light metals, and ultralight metals.

Metal Extraction

Metals are found in the Earth’s crust. A minority exist in their free form (native metals). The majority are combined with other elements, forming minerals. These minerals are represented by chemical formulas (Metal + Non-metal). The main sources of minerals are sulfides and oxides.

  • Ore: A mineral with a high enough concentration of a metal to make its extraction profitable.
  • Gangue: Mineral residue left after the metal is extracted from the ore.

Extraction Techniques

Metals can be extracted from ore in two main ways:

  1. By Heat: Based on differences in density and melting point. Denser metals remain at the bottom of the furnace. Additives like carbon can bind to nonmetals.
  2. By Electricity: Based on differences in charges (metal + non-metal), by applying an electric field. This method is typically used for light metals.
Steel

Steel is an alloy of iron and carbon (Fe + C). It improves the properties of iron, offering high tenacity, high plasticity, and high resistance to corrosion.

Titanium

Titanium is the fourth most abundant metal in the Earth’s crust, although its extraction is expensive. It is as hard as steel but 45% lighter, and 60% heavier than aluminum but more than twice as strong. It also exhibits high resistance to corrosion. Titanium technology has developed since the mid-20th century, with applications in aerospace technology and medical instruments and prostheses.

Coltan

Coltan is a mixture of two minerals: columbite and tantalite.

  • Columbite: Niobium ore (used in magnetic components, such as hard drives).
  • Tantalite: Tantalum ore (used in the manufacture of rechargeable batteries). It is a strategic asset due to its scarcity, essential for industrial production, lack of substitutes, and difficulty in recycling.

Polymers

Polymers are macromolecules: large molecules composed of repeating chemical units called monomers.

Types of Polymers

  • Natural Polymers: Starch, silk, etc.
  • Artificial Polymers: Nitrocellulose, vulcanized rubber.
  • Synthetic Polymers: Plastics.

Properties of Plastics

  • High plasticity, elasticity, and mechanical resistance.
  • Electrical insulation properties.
  • Cheap and easy to produce.
  • Inert and very durable, leading to degradation challenges.
  • Produce toxic substances when burned.
  • Can be sterilized.

Uses of Plastics

  • Packaging
  • Construction
  • Non-stick coatings
  • Waterproof fabrics and fibers with special properties
  • Missile caps

Plastics have replaced traditional materials in many applications and have become indispensable in some cases.

Classification of Plastics

Plastics are classified based on their properties and uses, such as for packaging.

Nanotechnology

: is the technology that allows one to manipulate atoms uno.MONOCOMPUESTOS CARBON “Futereno (structure of a ball of futbol) -> biomedical aplicacoines (vehicoles to transport molecuales inside the cells. “Nanotubes (futereno derivatives, so long) -> features: (a superconductive materials (transporting electrons from one end to another with no loss of energy). DEVELOPMENT OF TECHNOLOGY: “Fabrics: qu repel water and liquids in general, -Recubrimientos/pinturas: to repel other paintings,” Batteries: flexible, etc. ..