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Define Materials

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Sparweb

Aerospace
May 21, 2003
5,172
I'm not sure why this isn't in the Siemens 400-page user's guide. No instructions or rules about defining new materials for the materials library ESP file.
If someone can point me to a comprehensive guide to material definitions in FEMAP, then I could figure this out for myself.

My specific question is about units. Why do I sometimes see examples in ksi, MPa, psi, Pa? Does that imply that those users define their loads in kip, MN, lb, N, respectively?
Seeing "kilo" and "mega" and "milli" prefixes still doesn't seem consistent with the oft-repeated message that FEMAP is unitless.

No obvious method so "Save as..." The only offering is "save over top of the existing file"

The "Copy..." button allows me to create a new property from an existing one, but nonsensical values are pre-populated when I do this.

What values are optional for linear analysis with static loads and no variations in temperature?

Isn't the failure theory (Hill etc.) defined here? Can't find it. I've seen that check-box somewhere in FEMAP.

STF
 
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you can define any material you like and then save it to a library of your choice for later use, this way building a library of your own. Also, you can change the default library (which is standard set to use "old" units mainly used in the US) to one more of your liking (like international SI-Units). These pre-defined libraries are located in the femap directory. My solution is to remove the standard library and rename one using SI units, but of course you can set it in the program as well.
 
There is some info on creating/defining materials. Take a look at section 4.2.3 of the "commands" pdf in the "pdf" folder in the FEMAP application.
 
I've been plugging away at it (mostly by trial and error) and I think I'm getting somewhere. Like most other components of the software and NASTRAN, these files are completely readable by text-editor. This allows a certain amount of massive data entry without having to navigate the dialog boxes.

Now that I've looked around at the way these files work, I'm a little puzzled by the "little islands" that each of my company's stress analysts seem to be living on. I've spoken to a couple of them about sharing and compiling our materials files and they both had never heard of such an idea before. They each create their own properties files, plus plenty of other configuration files such as laminates, then they go on and on about how "so-and-so" made a model that doesn't work on their machine. To me it sounds like using common properties data is a necessary first step to collaborating and sharing work on a project.

Thanks TG, I'll go back to that section and see what I missed.

Unfortunately, at this company, I will probably not escape the chains of "imperialism", so to speak.

STF
 
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