Materials

Are the basic material from which goods that are extracted directly from natural objects.

examples: tree,

1.Raw materials

It can be classified in 3 groups:Animal Origin: come from animals: wool,silk…Vegetable origin:came from vegetables:

cotton,wood,cork…Mineral orgin:came from minerals: marble,clay...

1.2-Origins of raw materials

Materials are transformed by two process: phisycal process and chemical process into the various types of materials that are used formanufacturing

2.-Materials

-Physical process: Is when a substance changes its state, for example when a metal melts.

-Chemical process: Is when a substance is transformed into a different substance with different characteristics. Ex: petrol transformed to create some types of platic.

2.1.Physycal and chemical process

Is any object created by humans to satisfy their needs and improve their standard of living.

Examples:books,clothes,a sofa,glass, bottle...

3.-Manufactured goods

Common materials used to make manufactured goods:

Wood, metals, plastics, textils, stones and ceramics.

3.1-Technical materials

5-Properties of materials1.PHYSICAL PROPERTIES: To how materials reacted to external stimuli, e.g. electrical, light, heat or the applaying of various forces

2.CHEMICAL PROPERTIES:We can see these properties when the chemical composition of a material changes because it interacts with other materials.

3.ECOLOGICAL PROPERTIES:It can be recyclable, toxic and biodegradable

Electrical: electrical conductivity and electrical insulatorThermal: thermal conductivity and thermal insulatorAcoustic: acoustic conductivity and acustic insulatorMagnetic: Some metals attract some others and this is the

magnestism funtionOptical:opaque, translucent and transparentMechanical:mechanical strengh, elasticity,plasticity, malleability,

hardness, toughness, brittleness and ductility.Others: density,porosity, permeability and impermeability

5.1-Physical properties

Oxidation: this happens when a material reacts with oxygen in the air or water. Metals are the most sensitive materials to oxidation.

For prevent rusting are coated to with paint,varnish...

5.2-Chemical properties

*Recyclable:Are materials that can be reused(Glass,paper,metal…)

*Toxic:These are harmful to the enviroment(Mercuri,petroleum…

*Biodegradable:There are materials that descompose naturally and don’t cause damage to the enviroment

*Renewable: raw materials that can be regenerated: wool, cotton and wood.

5.3-Ecological properties