This content provides a comprehensive overview of various materials, their properties, and applications, designed to help students prepare for GCSE and A-level Design Technology exams. It covers a wide range of material categories, from natural resources like wood and textiles to manufactured composites, metals, papers, boards, smart materials, and polymers.
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hi guys this is a video covering a wide
range of materials that you need to be
familiar with for your GCC or a level DT
exams I'm luckily materials is a topic
that doesn't change too much once you
get to a level so the content overlaps
between GCC and a level I've listed the
material categories here that I'm going
to talk about physical versus working
properties Woods Composites Metals
papers and Boards textiles smart
materials and ending with problems two
disclaimers before I begin firstly I'm a
your 13 student making this video so if
there are any mistakes or Corrections
I'll list them in the description and
the comment section of this video though
I've tried my best to fact check
everything against textbooks my notes
and the internet secondly this video
covers many exam boards however not 100%
of everything will be applicable to you
so have your specification or your
revision list handy and check what
materials you need to know for your exam
okay starting off with the difference
between physical properties and working
properties so physical properties are
the traits a material has before it is
even used working properties are how a
material behaves when it's manipulated
when there's Force um added to it or
there's forces on it so some examples
include of physical properties density
which is basically the mass per volume
of a material the weight how heavy
something is the moisture content how
much water is in the material normally
in woods shrinkage when materials um
when when normally Woods lose water they
shrink sometimes thermal conductivity
electrical conductivity so ability to
conduct heat or or an electric current
the grain so the direction of like wood
grain is um a physical property color
the Aesthetics the color of material
texture transparency in normally papers
and Boards um to what extent like can
pass through that material chemical
resistance and absorbency then we have
working properties so stuff like
workability which is um how easy it is
to cut shape finish or even like carve
that material machine ability the ease
of being processed using machines um
stability so a lot of manufactured
boards are quite stable they don't warp
or twist easily abrasion resistance
flexibility tear resistance crease
resistance these are more in um textiles
or papers and Boards printability so the
ability to accept printed ink or images
most papers and Boards have good
printability so they can um basically
Graphics can be printed on um hardness
which is the resistance to scratching or
indentation the hardness is um different
to toughness um hardness is scratching
toughness is like shock um and other
forces so different types of strength as
well tensile strength compressive
strength elasticity the ability of a
material to return to its original shape
after being deformed and permeability
malleability ductility these two ones
are really common and then relability
and modability so in exams often you'll
see questions like explain one working
property off or give two physical
properties off um really common exam
questions and here are a list of your
physical properties and working
properties okay onto our first actual
material so Timbers or wood woods so
there's hard woods and soft Woods hard
woods come comes from Broad Leaf
decidious trees where soft Woods come
from coniferous trees like Christmas
trees they have needle like leaves and
softwoods are cheaper and faster growing
because the trees grow faster and then
Hardwoods um come from sort of trees
that have so bigger leaves okay so
there's five Hardwoods which I've
mentioned here Oak mokan jell Tong Beach
and BSA so these directly Cate with the
a level lxl specification and there's
four softwoods Redwood large pine Cedar
so starting off with oak oak is a hard
material which means it does not scratch
easily it's resistant to wear and te and
it has an attractive grain so this is a
piece of oak furniture it contains tanic
acid which will corrode steel fix things
so often it has to be finished so it
does not end up corroding um other
metals um it is the strongest and
densest hardwood so densest means it has
the greatest mass per volume it's used
in furniture barrels
Etc Hardwoods tend to have a close a
closer grain which means they carve
better because they're less likely to
split or splinter if you can imagine
softwoods have more basically holes in
them have um more empty space so they're
likely to Splinter Etc um then mahogany
has a dark red color it's duable stable
it's used in musical instruments in
cabinets Etc jell tongue um slightly
different hardwood it's um got a softer
texture soft spongy texture and it's
easy to work with hand tools it has a
load density and a lower durability
compared to the other Hardwoods it's
similar to BSA actually we'll talk about
a second but has a tighter grain so Bala
is a super lightweight um hardwood
people often think it's a softwood but
it's actually a hardwood it has a
straight grain low density light weight
it's used in model making so often in in
school you maybe you would have seen
this material um in like model airplanes
model houses for example here is an
example of like an architecture model
made with Bosa is super soft Norm almost
like you can um carve it with your
fingers you can snap it you can like
squeeze it quite um yeah a low density
material um and yeah it's actually a
hardwood even though it has sort of
softness and it's a lightweight material
okay and then Beach is the final
hardwood I'm going to talk about um has
a straight grain with a fine uniform
texture making it easy to work with it's
used in mallets it's used in children's
toys used in chopping
boards Beach is um yeah quite a hard
material and it has a sort of slightly
lighter color compared to Bren mahogany
so an acronym you can use to learn um
just the names of these um hardw is b o
m BJ BSA Oak Beach mahogany jelly okay
now to move on to softwoods so Redwood
large pine Ceda are the four you need to
know for specifically a for a Lev XL so
Redwood looks like this not so quite
common it's a lightweight material but
has good strength it's used in
structural components and eternal
decorative moding so for example
architraves um large is a hard tough
waterproof material but it's prone to
splitting so it needs to be pre-drilled
it's used in bow building fences Pine is
a very common softwood um it has a
straight grain it's naughty so quite you
can see um quite common property of
softwoods is that they're naughty they
have knots in them um and pine is
susceptible to what so it has to be
finished it's lightweight low density
and used in sort of basic furniture and
stools and so on and used in
construction then Cedar is quite
interesting softwood um it has this
slightly darker richer color to it it's
got natural resistance to Decay insect
infestation which is why it's used um in
outdoor cladding used in fences here you
can see outdoor chairs made from Ceda um
because it's naturally resistant to
Decay and rotting Etc so five Hardwoods
four softw um generic properties of
Timbers so for example hardness as we
said earlier is the resistance to
scratching workability how easily it can
be cut shaped car
strength here you can see five different
types of strength tension compression
share torsion bending so in bending
there's tension on one side compression
on the other side okay onto our next
material which is going to be Composites
so we have some timber timber based
Composites and some other of non-o based
Composites so starting off with MDF
super common material it has a smooth
surface it's dimensionally stable so
it's not likely to war because it's
man-made it's highly Su highly
susceptible to moisture damage and it
expands when it absorb water so yeah MDF
and water does not go well together you
have to finish it in some way to make it
waterproof to make it resistant to water
um it's easily shaped and it takes paint
well it has a really sort of nice
texture so it absorbs paint really well
a misconception is that it's lightweight
it's very common in the exam to say oh
material is lightweight MDF actually is
not lightweight it's really dense it's
heavier than a lot of Hardwoods as well
and it comes in large sheets which most
manufactured boards do um normally comes
in um 1.2 M by 2.4 M sheets then in
plywood which is similar to MDF it has
an odd number of layers so it's made up
in this layer form like this um the
reason it has an odd number of layers is
so the top and bottom grain direction is
parallel so three three layers five
layers Etc um it's a strong and stable
material similar to MDF it has a high
strength to weight weight ratio so it's
relatively lightweight for how strong it
is it's using Furniture Tabet Tre a lot
of different things and PID is probably
the material you're most familiar with
using it in school
it's available in various thicknesses so
normally in multiples of three so 3 6 9
12 Etc comes in large sheets um and this
is what it looks like so if you have to
identify it based on a picture this is
what ply looks like it has it very
visible layers then let's talk about
blockboard so blockboard is made from
solid wood strips or blocks like this
picture shows that are sandwiched in
between thin layers of wood veneer um so
relatively almost low quality material
but really strong um and used in
construction then
hardboard um it's used in the back of
wardrobe backing so if you can imagine
like having a freestanding wardrobe the
thin material at the back that's just
there as a show it just to um yeah to
provide the backing um that's normally
what hardboard is used in has a smooth
surface and it's tough even though well
I guess in the um wardrobes it's quite
thin material so you wouldn't
necessarily say it's tough then
chipboard is the S third most popular um
or like another manufactured board it's
strong in all directions it's really
strong it's made almost like MDF but
it's made in these um chips larger chips
it looks like this it's quite
unattractive as such um but the um
manufacturing of it makes it really
strong it's not attractive at all it's
used in flat pack furniture with veneers
so a lot of like Ikea furniture is made
from chipboard or even particle board
which is another type of chipboard comes
in large sheets and it's available in
various grades so you have chipboard
that's made for outdoor use it's
construction grade chip chipboard also
exists and comes in various densities
depending on what um like purpose you're
looking for and then so those are um
what is that five Timber based
Composites then we have two other ones
we have um carbon fiber reinforced
plastic and glass reinforced plastic
which are polymer based Composites so
carbon fiber and polyester resin gives
you carbon fiber reinforced plastic it's
this material here um it's lightweight
corrosion resistant tough has a low Thal
expansion and it's quite a stiff material
material
it's used in cars it's used in um yeah
sports equipment and it's made made
using the layup lamination process so
that's where you have um sheets or like
matting is called of um carbon fiber
it's pressed into a mold and then resin
is poured on top to fill the spaces and
this when the resin cures this
combination of having the fibers along
with the resin almost like paper mâché
is what gives it that hard shell like
structure and then glass reinforced
plastic similar thing using um glass
fiber and polyester resin it's
lightweight tough it's an electrical
insulator it's transparent to radio
waves it's used in boats in boat holes
water tanks and just like um carbon
fiber reinforced plastic is made using
the layup lamination process now to talk
about Metals we have um Ferris Metals
non- feris metals and Alloys so here we
have three Ferris Metals um a ferris
metal means has ion in it so this symbol
in the per table for ION is Fe that's
where the feris comes from um f Mets are
magnetic they can rust and they contain
iron so mild steel medium carbon steel
and cast iron are three types of feros
metals basically iron mixed with carbon
um so mild steel has has approximately
0.3% carbon in it it's also called Low
carbon steel it's ductile has a high
tensil strength it's tough It's
malleable um but it has a a poor
corrosion to resist to sorry a poor
resistance to corrosion it's used in
bolts car bodies and white goods white
goods are sort of appliances um that
normally have like a white like a frame
around it so this like washing machine
for example the body itself would be
made from low carbon steel and the white
comes from dip coating um so the reason
it's dip coated is to protect it from
rust because otherwise um the material
itself the mild steel would
rust um it's also mild steel is also
used in um like the polypop chair the
legs of your sort of normal school
chairs and again those are painted to
protect against rust medium carbon steel
has approximately 0.7% of carbon in it
it's harder than mild steel but it's
less ductile um it's malleable and it's
tough it's less malleable but it's
tougher it's used in gardening tools
machine parts a lot of like Gars and
bolts and stuff is used in um is what
medium carbon steel is used in and then
lastly cost iron is what your um bench
VI are made of and like manhole covers
so it's got hard outer skin however the
core itself is really
is is good under compression so of
course Ace itself is used to create the
compressive Force so you have um cost IR
good for compression um so with each all
three of these as you increase the
carbon content the strength and hardness
increases but it becomes more brittle so
brittle means um it can't resist like
really strong quick um impactful Force
so if you smash like a vice with like a
really strong Hammer um it would
probably shatter into like a load of
pieces so those are your three feris
metals and then we have a pair three um
Alloys so alloy is a mixture of two or
more types of two or more Metals um to
basically normally to enhance properties
so brass stainless steel and derum so
brass is an alloy of 65% copper and 35%
zinc it's corosion resistant it's an
electrical and thermal conductor it
costs well it's hard malleable and
ductile normally as we've seen if a
metal is malleable it's also duct tile
and then malleable means it can be um
almost hammer or shaped um without
fracturing and the dark to means it can
be pulled or stretched into some like
almost like a string or like like a pipe
like copper pipes are duct cuz copper is
a duct material it can be basically
pulled into a wire so here um we have
like almost washers or bols or something
that are made from Ross stainless steel
is tough hard corrosion resistant smooth
nonporous um all metals are nonporous it
means it doesn't absorb water it's easy
to wipe normally made from chrome nickel
silicone maganese and used kitchen wear
Cutlery a past question has been um
explained one property of stainless
steel which makes it suitable for
cutlery so you can say it is not it is
coion resistant which means that it will
not rust therefore it will be safe to
use with food um to giving a point
explanation and then linking it back to
the question so cery used with food
that's your three marks a three mark
question here um so that's St is steel
and then um jum is lightweight it's a
strong material cal It's Made From
aluminium copper and magnesium it's used
in aircraft and vehicle pots so those
are three Alloys then we have four um
these four here four non-fur metals
which do not rust are not magnetic and
don't contain iron so aluminium copper
tin zinc aluminium is lightweight
ductile malor um aluminium is the one
metal that for sure is lightweight it's
used in drink cans AO bodies bike frames
so for example here the bike frame made
from aluminium copper it's for te
resistant malleable ducto again we see
malleable and ducto together it's soft
it's used in wire electrical wire and
water pipes and yeah um because it's
also um a therond so it can carry heat
basically and then tin is ductile
malleable used in soft solder so
soldering um like welding it's used in
soft yeah soft solder used in circuit
boards um it's a coating for food cans
um and basically yeah it's used as a
productive coating the steel as it does
not rust so if you think about like
baked beans cans and stuff normally
sometimes um covered in tin to stop the
stainless steel from rusting and then
lastly zinc is has good corrosion
resistance used in buckets and a
protective coating for other materials
so um the big sort of Street pipes or
Street lamps
um they're often coated in zinc um it's
called it the process of galvanizing it
has that like almost um that metallic
finish to it that's what that's what
steel does and is also used in diting um
an acronym you may find helpful to
remember these four nonfer metals is
actz your aluminium copper tin zinc now
on to papers and Boards we have four
types of paper and six different boards
so layout paper um starting from the
thinnest is thin translucent so it's
used for transposing images used in like
architectural drawings um it's used in
sketch pads and it's around 50 g per
square met GSM so GSM stands for G per
square meter it is is used to measure
the mass of paper so for example 80 GSM
means that 1 square meter of that paper
weighs 80 g next up tracing paper is
slightly thicker than layout paper it's
used for copying images when drawing or
um seeing an image underneath so in mats
for example youd use tracing paper you
would have used tracing paper um at 60
to 90 GSM then copy of paper is
inexpensive general purpose it can be
colored so this is your standard a for
or printer paper it's used for general
office printing it's 180 GSM then
cartridge paper is the heaviest it's
off-white with a slight texture it's
used for sketching so this sketch pad
for example um has 50 sheets of 140 GSM
so that would be cartridge paper it's
between 120 to 150 GSM those are your
four types of paper going from the
lightest to the heaviest um then onto
boards we have mounting board it's made
from compressed cotton fibers it's used
for picture mounting or modeling then
corrugated board which is just your
normal cardboard it's made from cotton
board out outer layers and a corrugated
middle layer so this has the two sort of
thinner layers of col on the outside and
then this fluting is the main thing that
gives it it um its strength because
although the fluting can be compressed
downwards it's strong upwards because of
all the ridges it has so this would be
um so cardboard is strong in One
Direction weak in the other it's used in
protective packaging as it's able to um
provide protection against impact So
like um when you're moving house or the
boxes and stuff made from corrugated
board then foring box board is made for
multiple layers of Pulp um the top layer
is pigmented it has good printability
and it can be embossed so this picture
here shows embossing where there's like
a um a difference in layers difference
in texture so this process is called
embossing and folding box board is used
in packaging then F line board um is
used in the food and drinks industry um
it is a board with foil applied to
provide water resistance it's used in
drinks packaging and milk Cottons um
then solid whiteboard is a high quality
card which is smooth on both sides which
makes it good for printing um it's used
in greeting cards and packaging so for
example this here is just a a plain
greeting card made from solid by board
then phone board um lastly phone board
is has um a foam middle cord with two
outer layers of card and it's used in presentation
