Construction Materials: Types and Properties

• The presentation is about construction materials.
• Discipline will beat intelligence in the long run according to Yokoi Toru.
• Civil Engineering Faculty, Ing. Ludwing Pérez B. presents the slide show on the topic of construction materials.

Types of Materials

• The slide show covers types and classifications of different materials.

Early Materials

• Human interaction with materials began in the Stone Age when stones were hit together to create primitive cutting edges and pottery.
• With the discovery of copper, the Bronze Age led to metalworking and soldering techniques.
• The Iron Age came about once iron, tougher than bronze and moldable when hot, was discovered.

Material Properties

• Material selection depends on properties, forms to work them, its availability, cost, and environmental impact.
• Newer materials exhibit useful characteristics like Piezoelectricity and Superconductivity, where energy is not lost and magnetic fields repelled.
• Material properties include hardness, elasticity, tenacity, malleability, ductility, and mechanical strength advancements in engineering and construction.

Metallic Materials

• Metals either contain iron (ferrous) or do not (non-ferrous).
• Iron-containing metals are heavy and created with iron and steel-making technologies.
• Non-ferrous metals can be either light metals or ultra-light metals.
• Metals are extracted through underground mining or open-pit mining.
• Titanium can be used for aeronautics and medicine.
• Usages of non-ferrous metals like copper, bronze, and aluminum along with ferrous metals like steel can be seen in construction.

Polymers

• Polymers history: Celluloid was invented in the 19th century, Bakelite and PVC in the early 20th century, and Nylon/PVA/PS/PU, PE/PETE/ABS/PET/PC etc. shortly after.
• Categories include hard, strong, flexible, elastic, tension-resistant, and inert, along with natural, artificial, and synthetic varieties.

Material World and Quality of Life

• It examines the role of materials in defining social relations and living standards.
• It suggests that when opportunities arise it is important to be prepared with punctuality, responsibility, discipline, study, work and savings in mind.
• INDEC defines "poor" as families unable to afford basic food, clothing, and housing and defines "indigence" as lacking sufficient food for basic protein and energy needs.
• Poverty is defined as a condition where one lacks social necessities/income for both food and non-food needs, while extreme poverty is a state of lacking three or more necessities and having insufficient income to maintain well-being by still not being able to afford the necessary nutrients for a healthy life, even when allocating income to just buying food.

Evolution of tools

• Early humans likely considered tools and arms as primary material possessions, as societal eras were typically named for common materials used in tools/weaponry.
• 2 Samuel 12:31 mentions employing saws/thrills/axes of iron and brick kilns to force labor.
• Deuteronomy 19:5 references a tool that goes awry and harms a person, suggesting they can escape to cities to live.
• The Bronze Age marked the start of metallurgy around 2000-1000 BC, involving copper/tin alloys for enhanced tools/arms, and metal composition can change an element’s performance.
• The Iron Age is considered the period from 1000-1 BC and by 500 BC iron alloys widely displaced bronze.
• Despite clay not being a namesake reference to an era like bronze or iron, pottery has greatly improved descriptions of human culture for thousands of years.
• Glass objects can be traced all the way to ancient Mesopotamia around 4000 BC.
• Silicon-based electronics have had a great impact, but in the 20th century the culture was dominated by polymers, and was sometimes referred to as the plastic age.

Timeline

• The graphic illustrates the relative importance of various materials over time from before 10,000 BC to today.

Material Types

• The main types of materials are:
• Metals (steel)
• Ceramics and glasses (aluminum oxide and non-crystalline shapes)
• Polymers (plastics)
• Composites (fiberglass)
• Semiconductors (silicon)

Metallic Elements

• Structural steel is associated with engineering.
• Metals feature several key characteristics - strength, easy forming, ductility for impact resistance, metallic shine on a fresh cut, and electrical conductivity.
• Most elements that are inherently metallic on the periodic table serve as a base for alloys that make engineering materials.
• The most common are iron/steel, aluminum, magnesium, titanium, nickel, zinc and copper including brass (copper-zinc).

Ceramics

• Aluminum is a common metal, but aluminum oxide (Al2O3) which features in metal applications, is a type of ceramic.
• Aluminum oxide has two main advantages over aluminum metal that makes it appropriate for structural engineering because it is chemically more sturdy in a variety of conditions where metal would oxidize and, secondly, features a 2020°C melting temperature that significantly exceeds aluminum metal at 660°C.
• Aluminum oxide is a common refractory, resisting high temperatures in industrial furnace construction.
• Aluminum has high ductility, but does not support impact or bending.
• Silicon nitride (Si3N4) may allow high-temperature/high-efficiency motors, an unthinkable use case for standard ceramics.
• Ceramics structured at an atomic scale, however, are crystalline where their atoms are arranged in fixed patterns.
• Ceramics can be produced in non-crystal or amorphous form through processing techniques that make the solid non-fixed structure comparable to ceramics crystalline form.
• Non-crystalline solids with properties that can be compared to crystalline ceramics are called 'glass'.

Specialized Glass

• Fragility is a common trait of both glass ceramics.
• It can transmit visible light, ultraviolet, infrared and chemical inertness.
• Alternative categories of materials are composed of vitroceramics that are made of glass formulas (aluminum silicate of lithium), and totally devitrified by shifting state from glass, which includes a proper thermal treatment.
• The advantage for the compound aluminosilicate lithium is a low coefficient of thermal expansion that allows them to resist fracture caused quick temperature spikes that allow them to be commonly used as cookware.

Polymers

• Polymers describe the high conformability for a great number of polymers during production.
• These artificial, synthetic materials form a special branch of organic chemistry.
• A monomer in polymer is basically a single molecule of hydrocarbon, with the most common example being C2H2 or ethylene.
• Polymers are molecular structures that result as monomers are bound together and this commercial polymer is simply polyethylene, which is symbolized as (-C2H4) and also, with a "n" as a subscript that varies within 100 to 1,000.

Polymer Mechanical Traits

• The properties between the chemical bonds and the qualities of the substance (strength, ductility, temperature, and chemical reactivity) are important.
• The main mechanical property of polymers is that they tend to be lower in cost than the alternatives.
• Polymers commonly have lower resistance, fusion temperature, and higher chemical reactivity compared to ceramics.
• Many important polymers like polyethylene contain carbon and hydrogen, whereas other contain oxygen (acrylics), nitrogen (nylons), fluorine or silicon.
• Polymers can be categorized as plastics, elastomers and fibers.

Composite Materials

• The best composite contains reinforced fiber plastic that contains the highest qualities.
• A prime example is fiberglass (plastic reinforced with glass fiber) whereby the fiber's resistance plus the plastic polymetric matrix results in a sturdy material that can handle the structural demands of a material.
• Excellent natural material with useful mechanical characteristics based on structures that are reinforced by fibers like wood and concrete - mortar plus silicates reinforcing the complex matrix of cement.

Semiconductors

• Insulators: wood, plastic, rubber, fiberglass and minerals.
• Conductors: gold,copper, graphite, water, and iron.
• Semiconductors: silicon, carbon, germanium, and selenium of zinc.
• Semiconductors' electrical property means they are neither good conductors nor good insulators, instead having an intermediate capability to conduct electricity.
• Elements like germanium or silicon can be used with control over purity to obtain the desired electronic function.

Structures and Properties

• To comprehend structural properties, the architecture from atomic/micro scale must be examined that allows the material to have certain properties, plus crystal arrangement plus non-crystal ones as well.
• When you study the influence of material structures, keep in consideration that some alloys can be relative ductile whereby the aluminium allows ductility and the Magnesium is fragile.

Ductility

• Ductility relies less on mechanical performance depending on the atomic scale than the number four, which indicates deformation of a crystal that increases if you incorporate aluminum.
• The result is that the lightness for the alloys is a byproduct of adding magnesium to the formula
• Commercial ceramics are made by having powders heated under hot conditions which result in densification by forming porosity in the waste material.
• This can result in the loss of transparency due to it being dispersed among the particles.
• A12O3 or aluminum oxide can be added to pores that are not a refrangence source, which can improve the material.
• With only 3/10ths of 1% of porosity.
• Adding impurities by .1% mass can completely eliminate a high mass material.
• At a 1000-celcius rating can allow better illumination than the bombilla lights.

Processing

• The use of materials greatly depend on modern-day technology and its capacity for fabrication.
• Study of process materials will improve understanding on each material type, and allow appreciation the result of process history on the attributes of each type.
• This varies depending on design, whether it be a simple welding mold, or a electronic circuit.

Material Selection

• To obtain ultimate performance, consider cost, strength and ductility.
• First, select an appropriate material.
• Second, select the specific material within these options.
• Account for routine applications that include semi-conductors.
• Refrain from choosing materials commonly used and which have typically lower qualities.

Material-specific design consideration

• Some materials (like ceramics) are known to crack under some situations requiring a design that doesn't tax resistance and may not even prove cost-efficient.
• Metals generally have an issue of resistance coupled with ductility that proves excellent.
• Third cost requirement does not have a place for composites.
• The increase in cost is only justified during a very specific advantage - a reduced weight.
• Ductility relates to being changed without being harmed in any considerable manner.
• Tenecity means it will likely undergo some sort of change from one solid nature to the next - a fracture of module.
• Hardness has little or nothing to do with the ability of the material.

Considerations for specific use

• When choosing a material that contains only metals requires a lengthy list when deciding material for an important task, however you can narrow focus through price and if is commercially available, that has better qualities that is approved.
• The best properties are concentrated in the option that combines a resistance that is well rounded between cost and elasticity.