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Last edited 20 Feb 2024

Types of materials

[edit] Introduction

This is not a definitive guide to materials but it will help readers understand some of the basic components that go together, often as mixes in alloys, compounds or composites, to make modern construction materials. With the onset of climate change and the need to reinvent many materials to reduce impacts or increase possibilities to lock-in carbon some understanding of how these separate parts might fit together can be useful. Hyperlinked terms give further information on specific materials, with a wider selection found under construction materials.

[edit] Metals

[edit] Ferrous metals

Ferrous comes from the Latin word ‘ferrum,’ which means ‘iron. Metals which contain iron are magnetic, easy to work with, relatively inexpensive, incredibly strong and durable but prone to rust. Examples are:

Steel.
Cast iron - produced when a carbon content of 1.5-4% is alloyed with iron.
Wrought iron.

[edit] Non-alloy steels

Called carbon steels, they use carbon as the alloy (sometimes also manganese, silicon, sulphur, and phosphorus in small amounts):

Low carbon steel (mild steel) - less that 0.25% carbon - for nuts and bolts etc
Medium carbon steel - below 0.6% carbon - for parts under pressure like gears.
High carbon steels - up to 1% carbon - for springs, rail roads, tools and wires.

[edit] Alloy steels

Stainless steel is often produced through an alloy with chromium.
Stainless steel is also produced through an alloy with nickel.
Manganese alloys are good at higher temperatures.
Silicon can improve magnetic qualities.
Vanadium helps with shock resistance.
Molybdenum works well at high temperatures and against corrosion.

[edit] Non-ferrous metals

Non-ferrous simply means not containing iron. These metals are non-magnetic, lighter, sometimes more expensive, malleable, in part easier to fabricate and easier to recycle.They have high resistance to corrosion, good thermal and electrical conductivity, low density and are to some extent more colourful. Examples are:

Aluminium - used widely due to low weight, corrosion resistance, and ease of machining. It is a relatively expensive material, but can be multiply recycled, it is often the base metal for alloys and is used extensively in construction.
Copper.
Lead.
Zinc.
Silver.
Gold.
Titanium.

[edit] Non-ferrous alloys

Non-ferrous metal alloys may require a finish for protection or to improve appearance, but alloys can be either ferrous or non-ferrous in nature. Two common non-ferrous alloys are:

Brass (copper and zinc).
Bronze (copper with aluminium and / or nickel / tin).

[edit] Minerals

There are more than 3000 different minerals in the world, each made up of the same substance throughout. They derive from either a single chemical element or a combination of chemical elements.

Rocks (or stone) are made up of 2 two or more minerals. Granite is a mixture of quartz, feldspar, and biotite.
Ores are minerals that contain significant enough amounts of metals to justify extraction.

[edit] Rocks by physical classification

[edit] Stratified rock

Sandstone- a sedimentary rock of sand or quartz grains.
Limestone- a sedimentary rock, rich in carbonate made of calcite and aragonite (calcium carbonate).
Slate - made up of clay or volcanic ash.

[edit] Unstratified rock

[edit] Rocks by geological classification

[edit] Sedimentary

Sandstone - a sedimentary rock of sand or quartz grains.
Limestone - a sedimentary rock, rich in carbonate made of calcite and aragonite (calcium carbonate).

[edit] Metamorphic

Marble
Slate - a metamorphic rock from shale type sedimentary rock made up of clay or volcanic ash.

[edit] Igneous

Plutonic rocks

Granite - an igneous rock common plutonic rock rich in feldspar.

Hypabyssal rock

Dolerite - igneous rock, containing plagioclase, pyroxene, and olivine.
Microgranite - an igneous rock composed of minute crystals of quartz and alkalic feldspar.

Volcanic rock

Basalt - volcanic rock, columnar structure, typically composed largely of plagioclase with pyroxene and olivine.

[edit] Rocks by scientific classification

[edit] Siliceous

Siliceous are sedimentary rocks, very rich in silica or silicon dioxide. The most common siliceous rock is chert.

[edit] Argilaceous

Argilaceous are sedimentary rocks composed of clay size finer particles of aluminosilicate and other clay minerals such as kaolinite, chlorite. Claystone and shales are the most common.

[edit] Polymers

[edit] Natural polymers

Cellulose - a molecule, of hundreds or thousands of carbon, hydrogen and oxygen atoms. It is the main substance in the walls of plant cells, helping them to remain stiff and upright. Humans cannot digest cellulose, but it is important in the diet as fibre.
Nucleic acids - complex organic substance present in living cells, especially DNA or RNA, whose molecules consist of many nucleotides linked in a long chain.
Proteins - chemically, protein is composed of amino acids, which are organic compounds made of carbon, hydrogen, nitrogen, oxygen or sulphur.
Carbohydrates - Organic compounds occurring in foods and living tissue that include sugars, starch, and cellulose. They contain hydrogen and oxygen in the same ratio as water, and can be broken down to release energy.
Natural rubber - made from liquid tree sap, latex, from a variety of trees and plants, mostly Hevea brasiliensis.
Chitin - a structural polysaccharide found in the exoskeletons of crustaceans and insects and in funghi, where it creates cell walls, such as cellulose in plants. It is deposited extracellularly with proteins and other molecules.

[edit] Semi-synthetic polymers

Mainly derived from cellulose, these are natural polymers modified through artificial chemical treatment.

Cellulose acetate - partially acetylated cellulose, an insoluble heat-resistant and less hygroscopic cellulose derivative regarded as a non toxic, non irritant, and biodegradable.
Rayon - also called viscose, a semi-synthetic fibre, made from natural sources of regenerated cellulose, such as wood and related agricultural products with the same molecular structure as cellulose.
Nitrocellulose - also called cellulose nitrate, a mixture of nitric esters of cellulose, a highly flammable compound the main ingredient of modern gunpowder and used in certain lacquers and paints.

[edit] Synthetic polymers

These are polymers obtained from chemical processes, derived from petrochemical sources such as petroleum and oil.

Vulcanised rubber.
Nylon.
Teflon.
Bakelite - the first synthetic plastic.
Neoprene - a manufactured form of rubber.
Polyester.
Rayon - a manufactured form of silk.
Polyethylene - plastic bags and storage containers.
Polystyrene (packing and Styrofoam).
Epoxy resins.
Silicone.

[edit] Non-polymers

Elements - more than one hundred substances that cannot be chemically interconverted or broken down into simpler substances. The primary constituents of matter. Each element is distinguished by its atomic number, which is the number of protons in the nuclei of its atoms.
Metals - see above.
Ionic compounds - formed by ions bonding together through electrostatic forces. A simple example is salt, others are lithium fluoride / chloride / bromide / iodide and sodium fluoride / chloride / bromide / iodide.

[edit] Ceramics

Ceramics are non-metallic inorganic solids and can be classified into monolithic ceramics which are composed of a single chemical compounds and composite ceramics which are composed of multiple chemical compounds, there are different ways to further classify ceramics, which are given below.

[edit] Ceramics by composition

Silicate ceramics- manufactured mostly from natural raw materials; porcelains, steatite, cordierite and mullite.
Oxide ceramics - inorganic compounds of metallic or metalloid elements such as aluminium, zirconium, titanium, magnesium and silicon with oxygen.
Non-oxide ceramics - have much better electrical conductivity and are harder, such as nitrides, carbides, boride.
Glass-ceramics - combined materials that form a product between glass and polycrystalline ceramics.

[edit] Ceramics by application

Glass - can be called as a type of ceramic, known to be a non-crystalline amorphous solid material.
Clay products - bricks, roofing and flooring tiles, earthen ware, sanitaryware, stoneware and porcelain.
Refractories - substances that are resistant to heat.
Abrasives - used to grind or cut away other softer material.
Cement.
Advanced ceramics - alumina, aluminium nitride, zirconia, silicon carbide, silicon nitride and titania-based materials. They offer a high-performance, economic alternative to glass, metals and plastics.

[edit] Composites

[edit] Matrix phase composites

Metal matrix composites (MMC) - also called metal matrix composites (MMC) for cylinders, pistons, brake and disc parts of engines, carbide drills, tank armour, bike frames, sporting goods and jet landing gear.
Ceramic matrix composites (CMC) - used in gas turbines, thermal protection, heat exchangers, fusion reactors.
Polymer matrix composites (PMC) - either form thermosets (epoxies, phenolics) or thermoplastics (low density polyethylene (LDPE) or high density polyethylene (HDPE), polypropylene, nylon and acrylics.
Carbon matrix composites (CAMC) also includes carbon carbon composites and composed of carbon fibres and matrix phases (such as coke, sintered carbon and graphite) with characteristics of low density, high mechanical strength, high thermostability, high electrical conductivity and high thermal conductivity.

[edit] Dispersed (reinforcing) phase composites

Particulate composites - being composed of particles suspended in a matrix that can have virtually any shape, size or configuration. Examples are concrete and particle board. Two subclasses are flake and filled/skeletal.
Fibrous composites - consist of lightweight, high modulus fibres imbedded in a surrounding material. Examples are fibreglass and wood-plastic composites (WPCs).
Laminate composites - layers of different materials bonded together with adhesive, to give added strength, durability, or some other benefit.