Name the four main families of engineering materials.
metals, polymers, ceramics, composites
What manufacturing process melts metal to shape it?
casting
Which material can be recycled almost indefinitely?
metals
Name two key resources used in manufacturing.
energy, materials, water, chemicals
Name one type of manufacturing pollution.
air, water, soil, noise, thermal
Which material family has the highest hardness and temperature resistance?
ceramics
Which process removes material to obtain shape?
machining
What type of recycling melts plastics and reshapes them?
mechanical recycling
Which stage usually consumes the most energy: primary, secondary, or tertiary?
primary
Which emissions are common in ceramic firing?
NOx and SO₂
What component provides strength in a composite?
reinforcement
Which processes have higher material efficiency: forming or machining?
forming
What recycling route is most common for ceramics?
crushing as aggregate
What concept describes resources used per product?
resource intensity
What type of waste are machining chips?
solid material waste
Which materials are most difficult to recycle
What type of process converts raw materials into engineering materials?
primary processes
Why are composites difficult to recycle?
matrix and reinforcement are bonded
Why does recycling reduce resource use?
reduces raw material and energy demand
Why does high energy use increase pollution?
more fuel combustion and emissions
Why are ceramics difficult to recycle?
they cannot be remelted and are very hard/brittle
Why does machining generate more waste than forming?
material is removed as chips
Which material type has the highest circularity potential?
metals
What manufacturing approach aims to keep materials in cycles?
circular manufacturing
What is the most preferred option in the waste hierarchy?
prevention