ben1793

Does cold rolling effect the crystal structure of a material?

I am reaearching on materials and had a few questions about ceramics, I read that the amount of water in the clay is important when using proceses like slip casting, spraying and pressing, I was wondering is there anything else that would be effected apart from the clay shrinking due to the amount of water in the clay mixture?

Thank you so much, made it very clear and easy for me to understand.

Ok, thanks I understand it better now, but back to ordionary composition consisting of matrix and renforcements, how would the ratio of matrix/reinforcement effect the strength of the composite material?

Just like plywood are all laminates layered up at a right angles?

Thanks for the help, I looked into plywood and I read that the layers where all plywood (the same material) I thought that the whole point of laminates was to combine the properties of 2 or more materials combined to combine both properties for example like the windshield of a vehicle, I read that it was a combination of glass and hard plastic. Unless the information I read was incorrect?

Thanks for the reply, the example you gave made it much more easier to visualise. I looked further into composite materials and started reading about laminates, would the lay direction of laminates effect the material?

So I have been reading up on composite materials and have been geting a bit confused, from what I have read, composite materials consist of a matrix and reinforcement, the reinforcement can be fibers, I read that the way the fibres are placed will effect the machanical properties of the material does anyone know how this will be effected?

I am doing an engineering course at college and got some information on what I wanted to learn, I saw a question regarding D'Alembert's priciple and didnt know what it was about, for example it was a question that looked like this: mass x accelerates uniformly from rest to celocity of x in x seconds while ascending a 1 in x gradient, resistence is xKN making use of D'Alberts principle determine the tracktive force between wheels/road, the work done ascending the slops, the average power developed by the enginer. I am interested in how the principle works and how it would answer this sort of question, does anybody know of any good websites I could use to learn this principle? I tried finding it but end up finding stuff I do not understand, is this a advanced principle?

Its ok, it was just a question I have been wondering about since I have seen peizo materials, I will make a thread on the engineering forum, thank you for your help.

Thank you so much for your help, I would have never understood this without learning from you, thank you. I just ran into something and really wanted to know about it, I enjoy working on cars as a hobby and they have something called a lambda sensor, this tells the car computer system how much oxygen is in the exhaust system, now I was researching smart materials and ran into something called peizoelectric materials, the lambda sensors on the cars used ziconium dioxide, this material reacts to the oxygen creating a voltage, would this also be classified as a peizoelectricl material? Sorry I would have asked this question on yahoo but I have reached my daily limit and was wondering if you would know about this. Thank you.

Does fibre glass have a crystal structure or is it amorphous? (Does it matter what type of polymer is being used for the structure? I am using epoxy) Do shape memory polymers have a atomic structure and a crystal structure?

Does fibre glass have a crystal structure or is it amorphous? (Does it matter what type of polymer is being used for the structure? I am using epoxy) Do shape memory polymers have a atomic structure and a crystal structure?

Thank you for your help. Does the Epoxy Fibre glass have any crystal structures or is it amorphous? Also what is a commonly used polymer for shape memory polymers that would be suitable for my research?

I went on the epoxy link and found this, how would I draw it, what are the hexagons, what is the OH, does the O stand for oxygen or somethin else? Is there any crystal structures for the fibre glass epoxy? Also, would you not know of any advantages for the trigonal strucure such as the structure would make the material brittle, like you said in the past graphite is a layered crystal structure so it is very brittle and breaks easy.

I was looking at the trigonal structure for the quartz crystal, do you know of any advantages or disadvantages of the structure? Also you said the atomic structure never changes only the crystal structure will change, would this be the same for fibre glass? Is there no way to get pure fibre glass without any added atoms? What would be the most common structure for fibre glass? Thank you

I just had a look at the diamond and graphite structures and it amazes me that they both are made of carbon atoms and just because the structure is different one is the hardest material known to man and the other is the weak material used in pencils...WOW Thank you for the help So would it be possible to draw polyethylene as an atomic structure: I mean I could draw two carbon atoms with four hydrogen atoms but how would I draw the ( )n

Ahhh, thank you, never realised that I will use the link you sent me for the images of the alpha, beta crystal stuctures. After looking at what you said about the crystal structure being related to atomic structure, would this mean just like crystal structures change at different tempratures the atomic structure would also change? I am also wondering, how would the sturcture effect the strength of the material for example I mean like the alpha and beta crystal structures for quartz, how would the different structures effect the strength and other properties of the material?

haha, never knew about wolfram till you told me, its AMAZING. So you said for quartz crystal the atomic structure is SiO4 in an earlier post, so does this mean 1 silicon atom and 4 oxygens? So I am able to draw this just like I did for SiC by doing 1 silicon atom combined with 4 oxygens?

Thank you for your help, dont worry about it your health is much more important than my questions Hope you get better soon

THANK YOU THANK YOU THANK YOU, YOU ARE A GENIUS! I was wondering about the covalent bonds, from looking at what you said and doing some more research I found that all atoms want to become NOBEL so does this mean when I am doing silicon carbide I will have to add more than one carbon atom to the silicon to make 8 electrons on the outer shell of the silicon atom or do I only have to add one atom to the silicon for the example? Also the quartz crystal, I tried the link you gave me to find the atomic structure image (the one with the nucleus and electrons) but I could not find any, do you know any websites I could try or do you know anywhere where I could find one, I think the dificulty may be because it is a compound (I think) and that means I will be needing to do the same thing I am doing with silicon (find all the atoms and create a covalent bond). Also, fibre glass, I have come to a conclusion after doing a great deal of research that this is also amorphous (without shape) so I will not find any crystal structure for this, is this correct? I have also realised that this is a compound and in your last post you said this consists of many materials, is there a way I could draw just fibre glass in a atomic structure with a combination of atoms combined with covalent bonding? AGAIN...just want to say thank you, I have a week off and can not contact my teachers for help, you have been so much help

This is an example of what I meant about drawing the covalent bonds:

Thank you for the help The quartz crystals: Alpha: http://cst-www.nrl.navy.mil/lattice/struk.picts/sio2a.s.png Is the alpha a Face Centered Cubic structure? EDIT: Done some more research, is this a Dimond Cubic Structure? or a trigonal crystal? Beta: http://cst-www.nrl.navy.mil/lattice/struk.picts/sio2b.png Is this the correct structure for Beta-Quartz? Also, what type of structure is this (FCC,BCC,SC)? I have been trying to compare with the chart I have but I cant find a resembalance. EDIT: DID SOME MORE SESEARCH AND FOUND THE BETA I HAVE SHOWN IS INCORECT, IT IS SUPPOSED TO BE HEXAGONAL, IS THIS CORRECT? What I read was that alpha beta and delta are crystal structures at different tempratures, will the tempreure range be the same for all the materials or for something like tungsten would the tempreture be different compared to beta-quartz? For the Silicon Carbide is it possible to create a covalant bond with the atoms conected as images rather than text? I mean the images I had seen had two atoms conected by there electrons in the outer shell, would this be possible to do rather that the polyethelene example you had give because I need to draw them with the atoms and nucleus, I will give an example of the method you explained also but I am not sure if it is possible or not to do it directly with the atom diagram. Also, like you said the silicon carbide crystal structure has about 250 different crystal structures, I did some research and found the 2 most common ones, the alpha and the beta structures. alpha: Hexagonal Beta: Cubic Alpha is formed at temperatures above 1700 C and the beta is under 1700 C Is this correct? Thank you so much for your help.

I have done some more research and also talked to my lecturer before the holidays and found that like you said in the past, some of the materials I have listed are without shape (no crystal structure), did some research and found these were called amorphous, he said from the top of his head he could tell me that polyethelene has no shape, I asked him about the others and he said if he remembers right tungsten does (which was BCC) and quartz crystal does, that is all he knew off the top of his head but he said all he wants is the structure like tungsten which was BCC, he says just show the type of structure for example (BCC, FCC, close packed hexagonal, http://www.askiitians.com/onlinetest/studymaterial_images/1980_Crystal%20system.JPG), I am a bit confused now, I know tungsten and quartz crystal definatly have crystal structure but I cant find any for either quartz crystal or the others (GFRP, silicon carbide, shape memory polymer) are some of these also without shape(amorphous)? Also the tungsten, I did some research and found different forms of the crystal, I think the BCC which I found is alpha but there are also two others beta and delta I think, I found that these are different structures because of the tempreture effecting the structure, what would the crystals look like for beta and delta?(this is just extra knowledge for me ) Now from what you said tungsten is made from the same atom not a combination of many so it is a element, the other materials are made from a combination of different atoms so this means they are compounds? how would I draw the atoms for the compounds, for example for silicon carbie(SiC) would I get a silicon atom and carbon atom and draw them with a covelant bond? would the bonds for the materials be different because I did some research and found that there are different bonds, covalent, ionic and metalic bonds from what I read the covalant is where the outer shell electrons are shared, the ionic is when one atom gives another its electron making one positivly charged and one negatively and they attratact and the metalic is where the electrons are free and the posotivly charged atoms all atract to the pool of electrons, is this correct or have I been reading wrong? sorry for asking so many questions, hope it does not bother you, thank you for your help

thank you! I unerstand it now, you are also right about the fundimental chemistry course, I will look one up because I really need to get better at chemistry, until I get into a course I will probably do my research on the internet, I have 1 weeks holiday next week and I will be on the internet researching about chemistry. I am at college today and will ask my teacher about the atoms and see what he exactly wants, again thank you for your help would have never learnt anything without you