Engineering coursework help

[Repta]

Im strugling with some pretty simple structures calculations. Just dont know the formula needed. I need to work out:

Yield strength
Ultimate strength
Ductility Index at max load
True stress and strain at max load

I have load and displacement results and the area and length of aluminium and steel rods. Does anyone know the formulas needed?

Thanks

 

[Repta]

The formula is.....
...Pay attention in class.

I did but i dont have access to my notes at the minute and those are the only ones i cant remember. I did google it but so many different formula appear makes it pretty difficult to get the right one

 

[Repta]

Mechanical engineering?
Stress is force/cross sectional area
Strain is elongation/original length
Plot the stress strain graph then spot for yield strength and the other things I have no idea about .

Aeronauctical. Got the graphs and was going to just get the info from them but for some reason the cw spec ask for the formulas for calculating each to be written down, which has me stumped

 

[Repta]

With google and some searching you will find the right formulae. If you know the basics then you should be fine.

1st year I presume ?

Yea 1st year, can work most of it out from graph. Just a bit stumped that im asked to give formula for things like yield strength. Prob just a mistake in the coursework spec. Just going to use the graph as it what everywhere seems to be saying

 

[Repta]

Thanks for the help pretty much done now

This reminds me of all the boring stuff I was taught when I did aerospace engineering.

Im just hoping it gets a bit more interesting dont think ill ever find something more boring than fluid mechanics or stupid drawing lectures :/

 

[Repta]

Where about are you doing your degree? I only did this last year, and I can barely remember it. My heads to full of Castigliano's method, and bending moments and other fun stuff.

Loughborough, unfortuently i finding the course really boring so making things a lot more difficult

 

[Repta]

I found it a bit the same in my first year, since it was lots of rather uninteresting stuff. I'm not sure how your course is laid out, but now that I'm in my second year I find it a lot more interesting. I'm doing lots of interesting stuff now, like stealth and radar, and the design module is basically working in a group to conceive, design and model a UAV.

Everyone ive talked to has said it gets a lot better in second year and it seems to get better next term as well a bit. More design and workshop and a bit less theory. Guess ill find out soon.

Engineering Stress or Normal Stress?

Read the force off the graph and divide by the area... for 1 and 2.

N/mm^2 for 1 and 2.

extension over original length for strain?

I was doing this a week or so ago, really need to get ontop of my notes!

Thanks got it sorted now

 

[Repta]

Thanks that data book will no doubt come in handy