Welcome to the World of Material Science Preface: What is Material Science? Welcome to the World of Materials



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Welcome to the World of Material Science

Preface: What is Material Science?

Welcome to the World of Materials

Welcome to the world of science and engineering, and the application of discoveries in the world we live. Look around your environment and what is it that you see and experience. Can you identify any of these materials? Do you notice any tables, chairs, flooring, trash cans, books, or computers? There are items made of wood, metals, plastics, ceramics and combinations of these materials. If we are inclined to stay in a society where status quo is a way of life, many of the products we surround ourselves with would not be in existence. Are there any ideas on what have been major causes that have resulted in the in materials we have today?

In addition to new materials, society need understanding on how we implement these materials and what benefits do these materials give to our society?

Let’s look at a presentation by Ken Robinson. Sir Ken Robinson (born 4 March 1950) is an author, speaker, and international advisor on education in the arts to government, non-profits, education, and arts bodies. He was Director of The Arts in Schools Project (1985–89), Professor of Arts Education at the University of Warwick (1989–2001), and was knighted in 2003 for services to education.



http://www.ted.com/talks/ken_robinson_says_schools_kill_creativity.html

Notice the comment regarding the ability of educators to prepare student to a society that is unknown. We are to school the students to materials that haven’t been discovered yet.

Did you know….

http://www.youtube.com/watch?v=pMcfrLYDm2U

Material Science is an engineering course and is the only engineering course that is defined as both a science and engineering. There is Civil Engineering, Mechanical Engineering, Chemical Engineering, and now consider Material Science and Engineering.

Before we begin our journey into Material Science, we need to review some basic safety rules. Let’s look at the first power point found day one of week one. Once we complete the journey into safety we can then venture into the world of materials. The order found in the semester course or the year long course, are suggested paths to travel. Depending on the time allocated in the school year adjustments can be made. It is recommended to closely follow the suggested path until you have gone through the course entirely. Some activities may be omitted due to the lack of materials or costs. Note it may be necessary to annotate the missing/used material(s) so they can be placed on the inventory list for future classes. Remember to also keep current the amount of supplies you have so they can be replenished.

Journal
Introduction:

Welcome to the Science and Technology Journal. This document is a living text to be created by the students under the guidance of the instructor, who are taking the Science and Technology of Materials course. The students will create this Journal throughout the year by adding articles, presentation, free writes, lab reports and weekly reviews to the documents. To assist the students in the creation of this Journal, you the teacher must guide and instruct the students on the techniques that should be followed in each section. As you travel through the journal, notice the explanations associated in each section. As you touch the tab you will be directed to that page. That page will have a narrative description of the content to be found in that section. If needed, an explanation may be found describing the template to be followed. Let’s begin our investigation into the Science and Technology Journal.




Science and Technology Journal
Journal Prompts

1. What did this article make you think of?

2. What did you read that you did not understand?

3. What did you learn from the article?

4. What puzzles you about this article?

5. Do you agree or disagree with this article?

6. If you had one question to ask the author, what would it be and why?

7. What made sense to you about this article?



Language for learning is:

  • personal exploratory for the purpose of thinking, not testing incomplete a process, not a final product informal non-graded in the traditional sense


Journal Prompts:

1. I observed ........

2. My idea worked because ........

3. My goal in this project is to ........

4. Next time I’ll ........

5. My modification was to ........

6. The experiment was successful (unsuccessful) because ........

7. I wonder what would happen if ........

8. What did you do? think? feel?

9. What did you observe?

10.What was the most useful thing you heard in the last 30 minutes?

11. Write down what is bugging you.

12. What could the “stuff” be used for?

13. What was the “stuff” (material) like? What are its properties?

14. How did its behavior change/remain stable?

15. How is it different from similar “stuff”?

16. How would its properties be useful?

17. What did the “stuff” do?

18. Why do you think it does what it does?

It must be remembered there are NO WRONG ANSWERS! You intent should be to express your understanding of the topic being questioned. At times your free write will be based on your past experiences before any additional explanation is given. Other times it may be based on, what was taught it, and determine the level of understanding obtained.

E
Name_______ Lab Partners_____________________ Date________________


TITLE OF LAB

Objective: What is the purpose of this lab?

Procedure: How was the lab performed? Make sure to include the steps you performed. By reading this, an individual should be able to repeat the lab. Graphics and explanations may be included in this section. Graphics without explanations are NOT acceptable.
Data: This portion of the lab write-up includes any data collected during the experiment. The data may be included as tables, making sure to label all values with appropriate units. In addition, any and all calculations and/or observations are located in this section.
Conclusion: The conclusion is an important section of the lab report. It shows the final results and the understanding of the theory behind the results. Use this section to explain how the objective was met, or if it was not met, what were possible explanations. Explain any observations that were made during the experiment. If results are compared to other values, a percentage of error should be determined and cause of error must also be explained or justified.
ach Lab write up should have the name of all participants and the date of the lab
Title the lab… This may seem simple but it is essential to identify the lab
All Lab write ups should have:

Objective

Procedure

Data


Conclusion

The conclusion is the most import part of the write up. It should include whether the objective has been met or not. Use the information from the data portion of the write up to support your decisions. This write up should be factual.

Remember to ask “why?” did something occur and why you did what was done, and let this support your conclusive argument.

Articles

Throughout the semesters, articles will be distributed to the students and it is their responsibility to



1) Place the article in the Journal and

2) READ THE ARTICLE! These articles are support materials to the information presented, and the students are responsible for knowing what the articles contained. The articles can be included in the tests of the material to be graded.


Scientific Content

Scientific Content This section is for students to record the scientific content from the class. This will help them when working on weekly reviews and for reviewing for exams. Important Concepts should be placed in this section, including some worksheets that are distributed throughout the class.

Presentations

If the instructor chooses, they can distribute copies of the presentations to students prior to class. Depending on instructor preference, presentations can be distributed immediately before class or after the material has been presented. Students can take notes on the presentations. The presentations will be presented to the students with an option to with an area to the right where the students are able to take personal notes. These presentations with notes should be included in this section


Weekly Review

The purpose of the Weekly Review is to have the students integrate everything that has occurred throughout the week. Suggested outline of this weekly report can be:




Week _____ Topic ______________
Monday_________________________________________________________________________________________

Tuesday_________________________________________________________________________________________Wednesday_______________________________________________________________________________________

Thursday ________________________

________________________________

________________________________

Friday ___________________________

_________________________________

_________________________________

General Review____________________________

_________________________________________

_________________________________________





Week 1: Introduction to Safety?

Safety

It is essential to prepare all science classes with a review of safety. A power point presentation is available covering the topic. It must be stressed that clothing, safety glasses, and hair are a few points of discussion that could be listed as general safety procedures.

Glassware can result in cuts let alone injecting solutions into an open wound as a result of the cuts. Pouring materials into glassware is also a point to be considered. Prevention of “splashing,” drips, and thermal shock are major issues of considerations that can be prevented by simply erroring on the side of caution.

When dealing with chemicals, protective goggles is a must, as well as the usage of the safety techniques established in your previous chemistry classes such as waffling as oppose to smelling into a vial or test tube.

Heating is a common property that will be used throughout the course. We will be using various heating devices and it is essential that we maintain all levels of safety that are referred to in the power point presentation.

A safety quiz will be administered to verify awareness of the safety procedures established in this class.

Safety Power point

Safety Quiz

Let’s begin the investigation of materials.

Oobleck Experiment.

Purpose of the activity:



  1. making observations

  2. being open to the unexpected

  3. looking at properties

Materials:

  1. 5 oz. Dixie cups or plastics cups

  2. wood craft sticks

  3. water

  4. white powder (cornstarch)

Procedure:
1. Fill the Dixie cup approximately 1/3 to 1/2 full with white powder (cornstarch).
2. Add 1/3 as much water.
3. Stir with craft stick.
4. Consistency should be sort of like thick toothpaste or putty.
5. Go outside and experiment with the material.

Experiment with the substance:



  1. stir slow

  2. stir fast

  3. push the stick down through it – slowly and quickly

  4. squeeze it in your hand

  5. roll it into a ball and pull it apart

  6. hit a ball with a hammer

  7. play catch with

Journal:

  1. Describe the material

  2. How did you make it?

  3. What did you do to it?

  4. How did it respond/behave?

Teacher Information to describe to the students after the experiment is completed

This activity demonstrates



  1. a non-Newtonian material. It does NOT “obey” the laws of Newtonian physics.

  2. Oobleck displays a property known as dilatancy which is the tendency to become more rigid (solid) when it is stirred or subjected to a shear force or pressure.

  3. Therefore, Oobleck is known as a shear-thickening fluid (STF). Let the students experiment with the mixture before telling them that the white powder is cornstarch. This is a good opening day or first week activity to introduce journaling.

Class Discussion after experimentation and journaling:

What happened?



  1. A “correctly-made” batch of Oobleck should move like a fluid (liquid) when slowly stirred. It will be thick and viscous but “still flow”.

  2. When stirred quickly (more shear force applied), the mixture should “lock up” and behave like a solid. Upon sitting still, the mixture will return to its fluid state.

  3. If the craft stick is slowly pushed down through the mixture, little resistance will be felt and the stick will reach the bottom of the cup.

  4. If the craft stick is quickly rammed onto the surface of the mixture it will not be able to penetrate into the mixture which has become rigid due to the added energy (force).

Explanation?

  1. Cornstarch is a polymer which means it is made up of long molecules.

  2. Water and cornstarch do not mix real well. The starch doesn’t fully dissolve; it is more of a suspension.

  3. The starch molecule “rolls up” from both ends and becomes somewhat of a spherical shape that might resemble BB’s.

    1. Students seem to understand this when an analogy is made to a “slap bracelet”.

    2. When slowly stirred, the starch “balls” roll around each other and the mixture has fluid properties.

    3. When a larger amount of shear force is applied, the molecule uncurls and becomes more linear.

    4. These long molecules then entangle and the mixture becomes rigid like a solid.

    5. When the shear force is removed, the molecules move more freely and “roll” back up into balls which allows the mixture to flow like a liquid again.



-cornstarch in water without shear force -cornstarch in water with shear force

-like BB’s (spheres) -molecules uncoil and stretch out

-roll around and move like a fluid -chains become entangled and lock . up

Cornstarch does not mix well and will separate. This activity can be tied into a Forensic activity simply by adding some food coloring into the mix. Both physical and chemical properties can be illustrated in the Oobleck activity and an extension of the Oobleck activity can be made discussing the effects of Kevlar

Vocabulary:

Non-Newtonian - does NOT follow the laws of physics as described by Newton

Dilatant - adding energy (shear force) makes a liquid thicker or more rigid – more viscous

examples – oobleck (cornstarch-water mixture), liquid body armor



Thixotropic - adding energy (shear force) makes a solid thinner or liquefy – less viscous

examples – catsup, concrete, some paint Ralph Lauren, printer’s ink



Viscosity resistance or opposition to flow of a liquid

Options:

Have 3 different bowls of “powder” in separate areas of the room. Use cornstarch, flour, and plaster of Paris. Do not tell the students that the powders are different. Let them discover that the batches are not all the same and hypothesize and investigate why.

Make large batches of Oobleck and place it in shallow pans. Have students slap it with their hands or young children step on it.

Have students experiment to determine the “perfect” recipe for Oobleck while making and recording all measurements.

Another thixotropy and dilatancy lab may be found in the Battelle MS&T Handbook or CD beginning on page 4.4

Watch the YouTube video “A pool filled with non-Newtonian fluid” at



http://www.youtube.com/watch?v=f2XQ97XHjVw&mode=related&search

The students can read an article about liquid body armor and then write a short summary paragraph that relates it to the Oobleck lab they did in class.

Body Armor Fit for a Superhero –

http://www.businessweek.com/magazine/content/06_32/b3996068.htm

Liquid Body Armor –



http://usmilitary.about.com/cs/armyweapons/a/liquidarmor.htm

There are also several video clips about liquid body armor that students find interesting.

http://www.metacafe.com/watch/159764/liquid_armor/

http://www.nanooze.org/english/articles/article20_liquidarmor.html



There is a Dr. Seuss book about oobleck called “Bartholomew and the Oobleck”.

Articles are available to support the points on:



http://www.scientificamerican.com/article.cfm?id=enhanced-armor&print=true

Liquid Body Armor



Journal entries:

Describe the material.

+3 – white, thick, hard to stir and mix



How did you make it?

+3 – half cup of white powder (cornstarch) in a cup and added enough water to make a thick paste

Stirred with a craft stick until mixed.

What did you do to it?

+4 – stirred slow, stirred fast, pushed stick down slowly, pushed stick down quickly, played with it in my hands and rolled it into a ball, let it ooze between my fingers



How did it respond/behave?

+4 – flowed like a liquid when little or no pressure was applied – became stiff and hard like a solid when force or pressure was applied – shattered when hit with a hammer -



Reflect

+4 – one point for each specific idea

+2 – method completed

Total: +20 points

Week 2: Classification of Materials and Atomic Structure

Introduction to Material Science

An introduction of the course can be centered on the topic of “STUFF”. As previously discussed let’s review some materials found within the classroom. Let’s look a metals, plastics, composites and chrome. Why do we use these materials?

Well, can we make an attempt to define “Material Science?”
Materials Science is the science of all materials –


  • including ceramics, composites, electronic materials, metals and polymers

  • Emphasis on the study of the physical and chemical properties of matter

  • interdisciplinary –uses knowledge of physics, chemistry and biology applied to materials

The Materials Scientist



  • develops new materials

  • determines what materials to use

  • how to process the material into a useful component

  • ***this is a critical part of all manufacturing processes!***

As we investigate the world of Material Science one major point must be discussed….Where does the material come from?

If we believe that other factories or manufacturers are the source of the materials, we may be partially correct but there is another area that is more accurate…. The Earth.

Once we have the materials why do we need to further research the use of the materials?
Advancements in nearly every field of science and manufacturing depend upon the improvement and development of new materials.

So we can see that Material Science is an area of study whose findings are shared with many areas, such as the medical field, other engineering areas such as Metallurgy, Civil Engineering and Mechanical Engineering, and construction to name a few.

And what new discoveries does the Material Scientist use? The knowledge is based on Biology, Chemistry, Physics and Mathematics. Material Scientists investigate areas of metals, ceramics, polymers, composites and semiconductors, using applied knowledge previously learned.

Material Scientists investigate the relationship between Structure, properties and processing.



http://www.strangematterexhibit.com/whatis.html

Let’s take time to rewrite our comments regarding Material Science after the power point presentation and discussion on the NASA Article.

Power Point Introduction to Material Science

NASA article What is Material Science?



Classification of Materials

Our objective in this simple activity is to access student’s prior knowledge of materials. The students will be given a sample of material and they are to determine whether the material is a metal, ceramic, composite, or polymer. They are to defend their decisions. At no time is the student to be corrected.


Purpose:

  • To assess prior knowledge of students.

  • To generate interest in types and properties of materials.

  • To help students develop their own definition/description of each material category.

  • Practice Critical Thinking Skills: evaluating the materials and classifying and justifying the materials categories


Procedure

1. Hand out or have students choose an object(s) until all are taken

2. Each student’s task is to classify their object by putting it into one of the material categories and justify (give reasons) for their choice.

3. Generate lists on the board or overhead as students classify their object and give their reasoning. Be encouraging but do not indicate if their placement is correct or incorrect.

4. After all the objects have been classified, ask the students to count up how many objects they think have been put into the wrong category.

5. Go through the lists and make corrections.

6. As a class, generate a list of properties or descriptions for each category.
Notes and Suggestions:

• Students generally feel uncomfortable with this at first. They are not used to thinking out loud or having to give reasons for their answers.

• Rephrase what the student says so they can hear their thoughts


  • Do not give any indication if their answer is correct. The students start listening to each other and it is interesting to see how they are accepting of each other’s “opinions” as “facts”.

• Do not accept “because” as a reason. Insist that they give you more. Give them lead-in questions if they need help.

• If a student places an item into the polymer category and gives their reason as “because it isn’t a metal” – request more information, ask “how do you know it isn’t a metal?”

• If a student gives a response along the line of “because it looks like a metal” – request more information, “what does a metal look like?”

• Following is a list of sample items. Use whatever you find sitting around the classroom or home. It is a good idea to include some simple items along with some that are “ringers” (have no correct answer).

• Follow up with a discussion about the history of materials use. (see handout)

• Alternative method:



  • assign each material category a different location in the room

  • give each student an object to classify

  • have the students take their object to the material location they think their object belongs in

  • have the students at each material location decide who belongs/stays and who needs to go to a different category

  • have each group write a description and/or list of properties for their material category

  • share group results with entire class

• Alternative method:

  • spread the objects around the room

  • have the students classify each object on their own

  • place the students in small groups to discuss their “answers” and develop a description and/or list of properties for each material category

  • have a class discussion to develop a consensus on the classification of each object and to develop a final description for each material category


Sample Items: (make an ID Box)

Metals

Ceramics/Glass

Polymers

Composites

stainless steel foil

glass stirring rod

latex balloon

plywood

metal scoopula

brick

Fed Ex envelope (Tyvek)

cardboard

copper wire

glass bottle

preform

cotton cloth

aluminum wire




PVC pipe

Candle

steel wool




rubber stopper










Styrofoam cup
















Light Bulb - Assembly

Candle – polymer or composite








Light bulb – this isn’t a single material, it is an “assembly”. It is made up of more than one material and each material has its own function. The different materials are joined together but still are separate unlike a composite.
***candle – the students will want to place it under composite because of the wick. Remove the wick if possible or tell them just to consider the wax. Some scientists would not classify the wax as a polymer because the chains are too short. This is a good point of discussion.
Examples of student generated lists of properties for each category:


Metals

Ceramics/Glass

Polymers

Composites

hard)

not conductors

plastics

combination of 2 or more

Shiny Luster

High Melting T

Some are Natural




variable melt T°

brittle

some are absorbent




flexible

some are transparent

flexible




malleable

fragile

low melt T°




ductile

breakable

low density




good conductors

not workable

many are recyclable




heavy (dense)

formed by heat

stretchable




most are dense

sand or clay based

not brittle




opaque

fairly high density

bendable




undergo oxidation

poor conductors

rubbery




bendable

can be formed

expandable




strong

includes minerals

shrinkable




can be elements

can be recycled

elasticity




some are magnetic




some are transparent




fairly high melt T°




poor conductors




impermeable




can be easily formed




workable




long molecules




corrode easily




some are hard




come from ores

can be mixtures (alloys)






variety of properties made of compounds




Classification of Materials

Types of matter: element, compound, mixture

Types of elements: metals, nonmetals, semimetals

Types of structure: crystalline, amorphous

Types of bonding: metallic, ionic, covalent, intermolecular forces





Metals

Ceramics/Glass

Polymers


Type of Matter


Element or mixture

Compound or

Mixture of compounds


Mostly compounds



Type of Elements



Metallic elements

Metals with nonmetals

OR

Semimetals with nonmetals



Nonmetals


Type of Structure


Crystalline

Ceramics = crystalline

Glass = amorphous

Mostly amorphous with some regions of crystallinity


Type of Bonding


Metallic bonding

Ionic bonding and network covalent bonding

Covalent bonding and weak intermolecular forces














Classification of Matter

When classifying matter we begin with the defining matter and introduce the atom. Expanding the discussion we investigate solids, liquids, gases and plasma looking at their molecular structure.

Let’s fill in the table in the next slide based on what we just learned about the states of matter… (red indicate the answers)

What happens when heat is applied to the mass of various states of matter? If the solid state is below its freezing point and heat is applied, the temperatures rises following the behavior of Q= mcT. When it reaches its freezing point and heat is applied, the material begins to melt, however there is no temperature increase Q = mLf. A transition from the solid state to the liquid state occurs (fusion) at this point all of the material will become a liquid and only then can the temperature increase, once again using Q= mcT. When the boiling point is reached, and heat is applied, the material once again goes through a phase change, transitioning from a liquid to a gas and following Q = mLv. Finally when the transition is complete and the material is totally gaseous in nature, the temperature of the gas can increase using Q = mcT.





Atomic Structure and Bonding

What do we know about atoms and the periodic table? Take about 10 minutes, no more, to do a free write in the journal about your perception of atoms and the periodic table.

Discussions centers on the atom, discussing the nucleus, protons and electrons, and how each affects the mass of the atoms. The creation of ions and isotopes must be explained and associated with the bonding properties taught in chemistry.

Bohr Atomic Model :

Bohr proposed his quantized shell model of the atom to explain how electrons can have stable orbits around the nucleus in 1913. According to classical mechanics and electromagnetic theory, any charged particle moving on a curved path emits electromagnetic radiation, subsequently, in the Rutherford model the electrons were unstable; the electrons would lose energy and spiral into the nucleus. Bohr modified the Rutherford model by requiring that the electrons move in orbits of fixed size and energy. The size of the orbit controls the energy of an electron and is lower for smaller orbits. When electrons jump from one orbit to another radiation can occur. The atom will be completely stable in the state with the smallest orbit, since there is no orbit of lower energy into which the electron can jump.



Because an electron is continually accelerating in a curved path in orbit, according to classical physics, it should emit electromagnetic radiation (photons) continously. The resulting loss of energy implies that the electron should spiral into the nucleus in a very short time (i.e. atoms can not exist)



Bohr modified the Rutherford model by requiring that the electrons move in orbits of fixed size and energy. The size of the orbit controls the energy of an electron and is lower for smaller orbits

Bohr understood that classical mechanics by itself could never explain the atom's stability. A stable atom can be described by certain constants. The classical fundamental constants--namely, the charges and the masses of the electron and the nucleus--cannot be combined to make a length. Bohr noticed that the quantum constant formulated by the German physicist Max Planck, has dimensions when combined with the mass and charge of the electron, produce a measure of length. The measure is close to the known size of atoms. Bohr was encouraged to use Planck's constant in searching for a theory of the atom.

Planck’s constant was introduced in 1900 in a formula explaining the light radiation emitted from heated bodies. Classical theory states comparable amounts of light energy should be produced at all frequencies. This is not only contrary to observation but also implies the absurd result that the total energy radiated by a heated body should be infinite. Planck’s postulation was that energy can only be emitted or absorbed in discrete amounts, which he called quanta (the Latin word for "how much"). The energy quantum is related to the frequency of the light by a new fundamental constant, ħ. Heated bodies heated, radiate energy in a particular frequency range, according to classical theory, proportional to the temperature of the body. The radiation can occur only in quantum amounts of energy. If the radiant energy is less than the quantum of energy, the amount of light in that frequency range will be reduced. Planck's formula correctly describes radiation from heated bodies. Planck's constant has the dimensions of action, which may be expressed as units of energy multiplied by time, units of momentum multiplied by length, or units of angular momentum. Planck's constant can be written as h = 6.6x10-34  Joule seconds.

Bohr obtained an accurate formula for the energy levels of the hydrogen atom while using Planck’s constant. He theorized that the angular momentum of the electron is quantized--i.e., it can have only discrete values. He rationalized that electrons obey the laws of classical mechanics by traveling around the nucleus in circular orbits. The electron orbits have fixed sizes and energies. The orbits are labeled by an integer, the quantum number n.

Bohr explained how electrons could jump from one orbit to another only by emitting or absorbing energy in fixed quanta. If an electron jumps one orbit closer to the nucleus, it must emit energy equal to the difference of the energies of the two orbits. When the electron jumps to a larger orbit, it must absorb a quantum of light equal in energy to the difference in orbits.


Week 3: Atomic Structure and Periodic Table
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