## Materials Science C

parasaurolophus
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State: MI

### Re: Materials Science C

Hey guys, have you encountered any instances in which you had to calculate creep rate? I am finding some more complex equations that all involve calculus that are above the level usually included in Science Olympiad.
2017 MI State Champion of Chemistry Lab
2016 MI State Champion of Fossils

Past events: Chemistry Lab, Electric Vehicle, Materials Science, Robot Arm, Bridge Building, Fossils, Disease Detectives

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Joined: January 6th, 2017, 4:51 pm
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Location: Swarthmore College

### Re: Materials Science C

Hey guys, have you encountered any instances in which you had to calculate creep rate? I am finding some more complex equations that all involve calculus that are above the level usually included in Science Olympiad.
Yes, several times, though generally using given data points. Plot it to find the linear region (secondary creep), and your standard delta y over delta x usually suffices. I have yet to see a scenario involving calculus.
Lower Merion 2017
Subtitled: Revenge of the Non-Harriton

Placement Record:

Code: Islip | Conestoga | Tiger | Regionals | States
Out of: 61 | 42 | 36 | 37 | 36

Chemistry Lab: 9 | - | - | 4 | 4
Astronomy: 14 | - | 5 | 10 | 3
Material Science: 12 | 19 | 9 | 5 | 9
Optics: 14 | 7 | 3 | 4 | 2

Tesel
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Joined: January 30th, 2016, 8:03 pm
Division: C
State: MI

### Re: Materials Science C

So I've been doing Materials Science all year, I've got some good notes on the general properties section and on the materials characterization.

However, I'm struggling with the IMFs section.
What is a good textbook to find info about atomic packing and especially miller indices?
Also, anyone know a good source that explains detailed properties about various types of bonds?

Thanks.

2018 MI Mission Possible State Champions

parasaurolophus
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Posts: 30
Joined: December 30th, 2016, 8:23 am
Division: C
State: MI

### Re: Materials Science C

Hey guys, have you encountered any instances in which you had to calculate creep rate? I am finding some more complex equations that all involve calculus that are above the level usually included in Science Olympiad.
Yes, several times, though generally using given data points. Plot it to find the linear region (secondary creep), and your standard delta y over delta x usually suffices. I have yet to see a scenario involving calculus.
Thank you so much! So do Materials Scientists generally not care about the primary and tertiary creep? Or rather, for Science Olympiad purposes
2017 MI State Champion of Chemistry Lab
2016 MI State Champion of Fossils

Past events: Chemistry Lab, Electric Vehicle, Materials Science, Robot Arm, Bridge Building, Fossils, Disease Detectives

Proud 2016-2017 Co-Captain of the IA Central Gnomes

Skink
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Joined: February 8th, 2009, 12:23 pm
Division: C
State: IL

### Re: Materials Science C

So I've been doing Materials Science all year, I've got some good notes on the general properties section and on the materials characterization.

However, I'm struggling with the IMFs section.
What is a good textbook to find info about atomic packing and especially miller indices?
Also, anyone know a good source that explains detailed properties about various types of bonds?

Thanks.
Any text used for AP chemistry should have adequate coverage of intermolecular forces generally speaking and, hopefully, some bits on solid state chemistry (even if it's not being tested in ways it once was). After that, I find the chemistry texts inadequate relative to the introductory mat sci ones discussed herein, but they all contribute something.

Member
Posts: 66
Joined: January 6th, 2017, 4:51 pm
State: PA
Location: Swarthmore College

### Re: Materials Science C

Hey guys, have you encountered any instances in which you had to calculate creep rate? I am finding some more complex equations that all involve calculus that are above the level usually included in Science Olympiad.
Yes, several times, though generally using given data points. Plot it to find the linear region (secondary creep), and your standard delta y over delta x usually suffices. I have yet to see a scenario involving calculus.
Thank you so much! So do Materials Scientists generally not care about the primary and tertiary creep? Or rather, for Science Olympiad purposes
For Science Olympiad purposes I haven't been too concerned about it. I'm sure it's more important if you're actually an engineer.
Lower Merion 2017
Subtitled: Revenge of the Non-Harriton

Placement Record:

Code: Islip | Conestoga | Tiger | Regionals | States
Out of: 61 | 42 | 36 | 37 | 36

Chemistry Lab: 9 | - | - | 4 | 4
Astronomy: 14 | - | 5 | 10 | 3
Material Science: 12 | 19 | 9 | 5 | 9
Optics: 14 | 7 | 3 | 4 | 2

hearthstone224
Member
Posts: 132
Joined: October 13th, 2016, 1:50 pm
Division: C
State: IL

### Re: Materials Science C

Question on closed packed planes coming at you guys if you don't mind. This comes straight off a practice test and is as follows:

Give the Miller indices of a family of close packed planes in copper. Use the conventional notation indicating a family of planes.

1. What is a close packed plane?
2. Where is this plane (isn't it just from 0,0,0 to 1,1,1 the plane that is formed there?)
3. Why is the answer {1,1,1}? How do you just know that?

Ok Thanks for the help.
End of freshman season. Good luck to everyone! No state for us, but nevertheless great season. Regional was out of 12 teams. (CLC)

Mat Sci-> Second at regionals
RSensing -> First at regionals
Towers-> Third at regionals.

hearthstone224
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Posts: 132
Joined: October 13th, 2016, 1:50 pm
Division: C
State: IL

### Re: Materials Science C

So I've looked it up and apparently there was something called slip all along, with specific planes that are easier to slip (which I think basically means to break/plastically deform easier on) on and these planes are along the close packed planes. {1,1,1} seemed to be the first one they said. Should I memorize these planes? There really isn't a way to "derive" them, is there? Like you just have to know them?
End of freshman season. Good luck to everyone! No state for us, but nevertheless great season. Regional was out of 12 teams. (CLC)

Mat Sci-> Second at regionals
RSensing -> First at regionals
Towers-> Third at regionals.

younessnb
Member
Posts: 1
Joined: March 11th, 2017, 11:23 am

### Crystal Structure

Hello everyone! I'm hoping to see if anyone can help me figure out how to determine the crystal structure that will be formed or a given material There have been questions on the practice tests that ask us to figure out the crystal structure of materials such as sodium chloride and I am not too sure how to figure that out without memorizing the structures of the materials. Thank you so much for your time!

hearthstone224
Member
Posts: 132
Joined: October 13th, 2016, 1:50 pm
Division: C
State: IL

### Re: Crystal Structure

Hello everyone! I'm hoping to see if anyone can help me figure out how to determine the crystal structure that will be formed or a given material There have been questions on the practice tests that ask us to figure out the crystal structure of materials such as sodium chloride and I am not too sure how to figure that out without memorizing the structures of the materials. Thank you so much for your time!
Something that might help would be the wiki, which kind of helps to explain the 6:6 ratio coordination between Na and Cl. Basically it means you have sodium atoms surrounded with 6 other atoms.

I'm really not quite sure though, I think there is something related with the atomic radii, and then you actually take a ratio between them and then you can figure out how it is coordinated... Maybe someone else can help. Hope this helps, though.
End of freshman season. Good luck to everyone! No state for us, but nevertheless great season. Regional was out of 12 teams. (CLC)

Mat Sci-> Second at regionals
RSensing -> First at regionals
Towers-> Third at regionals.