Conversion of Material properties

Hello All,

I'm trying to setup some material properties for ASTM A500 Square Tubing,
however, SolidWorks is looking for N/m^2 and MatWeb doesn't seem to have a
conversion for this, only N s/m2 whatever that is.
Also, you apparently can't change the units from N/m^2. My VAR sent an
enhancement request in, and I will as well.
Anyway I'm looking for:

Elastic Modulus, Shear Modulus, Density, Tensile Strength, Yield Strength.
BTW, what are GPa & MPa units?

TIA,
Muggs

 

GPa is a GigaPascal
MPa is a MegaPascal

A Pascal = 1 N/m^2

1 PSI = 6894.757 Pascals,
or 6.894757 KiloPascals,
or 0.006894757 MegaPascals or
0.000006894757 GigaPascals

 

Great! Thanks Arlin,

Muggs

 

Please don't be offended by this, but what is your background/education?

Pa, MPa, GPa, and Psi are units that anyone with some rudimentary
training in strengths of materials should be aware of. If you don't
have much knowledge in this subject area, what do you need to use the
information for?

 

No offense taken.

I was a Modelmaker for about 15 years, then about 4 years ago I started
using SolidWorks with my company and started to do a lot of design.
We made toys and consumer electronics, so my background as a modelmaker
helped me in the design process.
Our "schooled" designers could often design something that would not work in
the real world, although it "looked good" on the screen.
So to make a long story short, because of my background as a modelmaker,
most of my designs "worked" right out of the box. And that did me well until
I got laid off this past October, so I'm on my own, and for the first time
designing things that are made out of materials other than plastic (steel
tubing for instance), instead of the more comfortable, injection molded
plastics design.
Also, to be honest, being a prototyping/model shop, material properties were
rarely a concern of ours. We basically knew that everything was going to be
make from ABS, HIPS, PP, etc.

So, anyway as to your question, I'll be using this info to get some
COSMOSXpress data on things like "will this thing actually hold 400#, or
not".

So as you can see, all of my schooling is from the university of "Seat of
the Pants".
BTW, This NG is a Godsend. I try not to ask questions that I can figure out
myself, but I'll admit, sometimes its easier just to ask here.

Thanks again,
Muggs

 

all of my schooling is from the university of

I figured as much. Just a word of caution/advice. FEA analysis does
require a good knowledge of strengths of materials (even though FEA
salespersons may try to convince you otherwise). Even seasoned FEA
experts back up their analysis with (crude) hand calculations just to
ensure the FEA is "in the ballpark."

I would highly recommend taking some strength of materials and FEA
courses to help your understanding. Things like fatigue, brittleness,
stress concentrations, etc. can have a HUGE impact on your design while
FEA often does not take such considerations into account.

While I certainly agree that design experience counts a great deal
towards good designing, if you are going to use analytical tools like
FEA, you need to know what it can AND CANNOT tell you about failure.

 

efunda (http://www.efunda.com) is a good site for engineering information of
all types and has units conversion page
(http://www.efunda.com/units/index.cfm?search_string=conversion).

HTH,

JJ

 

For some reason it has always been much easier for me to remember the
inverse of the above. One MPa=145 psi. (Well, 145.0377 and change, but I
hardly ever need four digit accuracy.)

Another great site for units of measurement is

http://www.unc.edu/~rowlett/units/index.html

This one really comes in handy for obscure old units.


Jerry Steiger
Tripod Data Systems

 

I usually remember 1 psi ~ 7 kPa
Not very accurate, but nice for in-head calcs.

I HIGHLY recommend this for unit conversion:
http://www.joshmadison.com/software/convert/

 

Please do NOT use COSMOSXpress for anything other than a seat of the
pants feel for the strength of a part. There is no where near enough
control or feedback to ensure that a proper FEA model has been
created.

FEA is not a trivial undertaking. Good analysts have years of
experience and of training. Just as knowing how to use Microsoft Word
does not make you a Pulitzer prize winning author, knowing how to use
COSMOSXpress does not make you an FEA analyst. I'm not trying to be
condescending here, but there is much more to FEA than meets the eye.

Thanks,

Chris