Materials, Manufacturing & Societal Impact
Natural Materials: Materials used as found in nature.
Processed Materials: Materials obtained by subjecting natural materials to various chemical processes.
Synthetic Materials: Materials obtained by chemical methods from other materials.
Technical Use Materials
Wood: Derived from tree trunks, strong, elastic, good heat and electrical insulator. Comes in natural (pine) and processed (plywood) forms.
Paper and Cardboard: Made from wood pulp, easy to cut, fold, sew, and dye. Available in various types like matte paper and folding cardboard.
Metallic Materials: Derived from minerals, conduct heat and electricity, and have a shine. Include ferrous (iron) and non-ferrous (aluminum) metals.
Plastic: Obtained from chemical reactions of oil and natural gas, good electrical insulators. Types include thermoplastics (PVC), thermosets (Bakelite), and elastomers (rubber).
Textile Materials: Formed from fibers. Properties depend on fiber length, fineness, and resistance. Sources include plants (cotton), animals (wool), minerals (flax), and synthetic materials (nylon).
Ceramic Materials: Obtained from rocks and sands. Hard, heat and electricity insulators, and resistant. Include ceramics and glass.
Electrical Lighting Production
Involves the union and assembly of simple parts.
Manufacturing Methods
Manual Fabrication: Using only hands, hand tools (scissors), or mechanized hand tools (drill).
Industrial Manufacturing: Takes place in facilities with specialized staff and machinery to produce large quantities of objects quickly. Uses large amounts of materials and energy.
Portable Machine Tools
Jigsaw: A reciprocating saw used to cut various materials.
Electric Drill: Used to drill different materials.
Fabrication Procedures
Procedures include adding material (molding), removing material (cutting), and joining materials (forming).
Deformation and Molding Processes
Folding: Bending a piece along one of its edges.
Drawing and Pressing: Deforming materials by force.
Forging: Deforming a heated metal block.
Drawing (Extrusion): Forcing material through calibrated holes of different diameters.
Rolling: Passing material between two rollers to flatten and polish it.
Extrusion: Pushing a plastic mass through an opening with a specific shape.
Extrusion Blow Molding: Extruding material into a mold and then introducing pressurized air.
Injection Molding: Extruding material into a mold formed by two parts fitted together.
Machining Processes
Drilling: Making a hole with a drill.
Turning: Carried out on a lathe.
Sanding and Rectifying: Smoothing and polishing surfaces using a sander. Rectifying refines and finishes the surface.
Quality Control
Aims to detect defective parts to prevent them from reaching the market. Can be performed throughout the production process.
Standardization
Facilitates obtaining spare parts and ensures compatibility between different components, even from different manufacturers.
Metrology
The science of measurement units, instruments, and systems. Its practical application is called metrology.
Caliper: The measurement is calculated by dividing the largest partition of the rule by the number of fractions on the cursor scale.
Accident Prevention
Accidents can occur unexpectedly or due to a series of unfortunate circumstances.
Environmental Impact
Factors to consider include materials used, energy consumption, emissions, discharges, waste, and transportation.
Limits to Growth
Limited by the planet’s capacity to provide energy and materials, and to absorb pollution generated by their use.
Societal Problems
Poverty, unemployment, and unmet non-material needs.
Necessary Actions
Facilitate development, slow growth, stop erosion, reduce consumption of non-renewable resources, and find alternatives.
Efficient Energy Use
Seeking and using alternative energy sources, increasing energy efficiency, and reducing energy consumption.
Waste: Materials that are no longer useful for their intended purpose.