Learning Materials
Features
Discover
It's estimated that $62 million worth of pennies are thrown out or lost each year. While that is a lot in total, losing 2 or 3 cents here or there doesn't matter to most people. In fact, people are trying to stop the mint from producing them, since we lose $70 million a year producing them. The material used in pennies is worth more than the penny itself!
Millions of flashcards designed to help you ace your studies
Sign up for free
Achieve better grades quicker with Premium
Geld-zurück-Garantie, wenn du durch die Prüfung fällst
Did you know that StudySmarter supports you beyond learning?
Review generated flashcards
Start learning or create your own AI flashcards
Team Structure, Composition & Properties of Metals and Alloys Teachers
Originally, pennies were made of just copper but were later made with a copper-zinc alloy due to rising copper costs. In this article, we will be learning about the structure of metals and alloys!
Before diving into the structure of metals and alloys, let's elaborate on the types of elements found on the periodic table. There are three types of elements:
metalloids
metals
non-metals
Periodic table sorted by element type. Wikimedia commons.
As you'll see in pink, there are a lot of metals, which are grouped based on the properties they share (which we will discuss later).
Metals can form alloys.
An alloy is a mixture of two or more metals or a mixture of a metal and a non-metal.
There are two types of alloys: 1. Substitutional alloys
2. Interstitial alloysIn a substitutional alloy, some of a metal's atoms are substituted by another element's atoms of a similar size. In an interstitial alloy, the smaller atoms of another element fill in the "gaps" in a metal's structure.
Now, let's talk about the structure and properties of metals and alloys. Metals are set apart by their unique characteristics. These include:
High melting point
Good conductors of heat and electricity
Malleable (can be bent/shaped easily)
Ductile (can be stretched easily without breakage)
High density
While you might assume that alloys share the characteristics of the individual metals they were made from, you would be incorrect. We typically create alloys as a way to "maximize" certain characteristics.
The difference between metals and alloys are:
Alloys are harder than component metals
Alloys are more resistant to corrosion than pure metals
Alloys have a lower melting point than component metals
Alloys are more ductile than component metals
Alloys are more durable than component metals
Alloys are less conductive than component metals
These properties make alloys more useful than pure metals. For example, steel (iron + carbon) is a common alloy used in building materials. This makes sense since it can hold more weight, is less likely to corrode, and can be more easily shaped than iron.
The overall structure of a metal alloy is dependent on its composition. Alloys can have different ratios of metals and can have several metals within them. Here is a chart with some common alloys and their compositions.
| Name of Alloy | Composition | Example of use |
| Amalgam | Mercury (45-55%), remaining (45-55%): silver, tin, copper, and zinc | Dental filings |
| Brass | Copper (65-90%), zinc (10-35%) | Door knobs and locks |
| Bronze | Copper (78-95%), tin (5-22%), remaining %: manganese, phosphorus, aluminum, or silicon | Statues |
| Cast iron | Iron (96-98%), carbon (2-4%), remaining %: silicon | Cookware |
| Gunmetal | Copper (80-90%), tin (3-10%), zinc (2-3%), remaining %: phosphorus | Guns |
| Pewter | Tin (80-99%), remaining %: copper, lead, antimony | Decorative items |
| Stainless steel | Iron (>50%), chromium (10-30%), remaining %: carbon, nickel, manganese, molybdenum, and other metals. | Jewelry |
| Sterling silver | Silver (92.5%), copper (7.5%) | Medical tools |
The atomic structure of a metal is pretty simple:
Structure of a pure metal. Vaia Original.
The atoms are neatly aligned and are all the same size. They don't necessarily need to be in a rectangle shape but are always evenly spaced and relatively close together.
Alloys are different. The atomic structure is dependent on the type of alloy: substitutional or interstitial.
Here is what a substitutional alloy looks like:
Structure of a substitutional alloy. Vaia Original
As the name suggests, one metal's atoms are being replaced with another's. These new atoms are similar in size to the other metal's atoms.
Then there are interstitial alloys:
Structure of an interstitial alloy. Vaia Original.
In an interstitial alloy, the second metal's atoms are much smaller than those of the pure, original metal. These smaller atoms fit in the "holes" of the original structure.
These types of alloys can be combined, so an alloy can have a structure that is a combination of the two shown above.
Metals and alloys typically have a crystalline structure. There are three main structures that a crystal can have:
Body-centered cubic (BCC)
Hexagonal closed packed (HCP)
Cubic closed packed (CCP)/face-centered cubic (FCC)
When we look at these structures, we often refer to the unit cell.
The unit cell is the smallest section of the lattice that shows the 3D pattern of the whole crystal.
Essentially, a crystal is just the same unit cell repeated several times. Metals and alloys form these structures since they fill space the most efficiently.
The first type of crystal is the body-centered cubic (BCC). Its structure is shown below:
Body-centered cubic unit cell and whole structure. Vaia Original.
The general shape is a cube, with an atom at each corner. There is also another atom at the center of the "body", hence the name.
Next, we have the hexagonal closed packed (HCP) structure:
Hexagonal closed-packed structure and unit cell. Vaia Original.
The unit cell for this type is much more complex. The top and bottom faces of the structure are hexagons, with an atom on each point and in the center. In the center of the cell is a triangle shape, with an atom on each point.
Lastly, we have the cubic closed packed (CCP)/face-centered cubic (FCC) structure:
Cubic closed-packed/face-centered cubic unit cell and structure. Vaia Original.
Like with the BCC structure, the basic shape is a cube. There is an atom on each corner and one centered on each face.
The individual crystal structures group together to form grains. These grains combine to form the grain structure, which can be viewed through a microscope. The image below is the grain structure for stainless steel.
Grain structure of stainless steel under a microscope. Wikimedia commons.
The size and orientation of the grains are dependent on:
The grains themselves are formed when the molten material solidifies. The grain structure is adapted for the application of the metal alloy. For example, cupro-nickel's grain structure is designed so that the metal can be pressed to make nickels and dimes.
Looking at the grain structure (also called the microstructure) can tell you the properties of the material such as strength, hardness, and ductility.
Sign up for free to gain access to all our flashcards.
How can alloying modify the structure and properties of metals?
Alloys are created to "maximize" the properties of metals. Alloys can be either substitutional (atom(s) of one metal substitute in for an atom(s) of a pure metal or interstitial (a metal's atoms fill in the "gaps" in the pure metal's structure).
What is the structure of a metal?
In a pure metal, atoms are closely packed together and are neatly organized to maximize space.
What are the differences between metals and alloys?
Alloys are harder, more durable, more ductile, and more resistant to corrosion than pure metals. However, they are also less conductive and have lower melting points.
What are the common structures formed when metals and alloys crystallize?
There are three common metal/alloy crystal structures. These are: body-centered cubic (bcc), hexagonal closed packed (hcp), and cubic closed packed (ccp)/face centered cubic (fcc).
What are 5 physical properties of metals?
Some properties of metals are:
At StudySmarter, we have created a learning platform that serves millions of students. Meet the people who work hard to deliver fact based content as well as making sure it is verified.
Lily Hulatt is a Digital Content Specialist with over three years of experience in content strategy and curriculum design. She gained her PhD in English Literature from Durham University in 2022, taught in Durham University’s English Studies Department, and has contributed to a number of publications. Lily specialises in English Literature, English Language, History, and Philosophy.
Get to know Lily
Gabriel Freitas is an AI Engineer with a solid experience in software development, machine learning algorithms, and generative AI, including large language models’ (LLMs) applications. Graduated in Electrical Engineering at the University of São Paulo, he is currently pursuing an MSc in Computer Engineering at the University of Campinas, specializing in machine learning topics. Gabriel has a strong background in software engineering and has worked on projects involving computer vision, embedded AI, and LLM applications.
Get to know Gabriel
Vaia is a globally recognized educational technology company, offering a holistic learning platform designed for students of all ages and educational levels. Our platform provides learning support for a wide range of subjects, including STEM, Social Sciences, and Languages and also helps students to successfully master various tests and exams worldwide, such as GCSE, A Level, SAT, ACT, Abitur, and more. We offer an extensive library of learning materials, including interactive flashcards, comprehensive textbook solutions, and detailed explanations. The cutting-edge technology and tools we provide help students create their own learning materials. StudySmarter’s content is not only expert-verified but also regularly updated to ensure accuracy and relevance.
Learn moreSave explanations to your personalised space and access them anytime, anywhere!
Sign up with Email Sign up with AppleBy signing up, you agree to the Terms and Conditions and the Privacy Policy of Vaia.
Already have an account? Log in
Sign up to highlight and take notes. It’s 100% free.
Explanations 
Textbooks 
Exams 
GCSE 
IGCSE 
AS 
A Level 
International A Level 
University Admissions Tests 
Flashcards 
Vaia AI 
Notes 
Study Plans 
Study Sets 
Find a job 
Find a degree 
Student Deals 
Magazine 
Mobile App 
