Add elasticity and density

[ipg-jsc]

Describe your changes

As discussed in the meeting on 04.09.2024:

• Add elasticity properties in form of Young's modulus and Poisson's ratio to material example
• Add density

Issue ticket number and link

Closes #58, closes #60

Checklist before requesting a review

• I have performed a self-review of my code/documentation.
• My changes generate no new warnings during the documentation generation.

[ClemensLinnhoff]

Looks good to me, thanks.
The only thing I am not sure about is which fields should be required. But I propose to go over all fields in the end and decide if they should be required or not.

[ClemensLinnhoff]

@AsamDiegoSanchez @drsftx73 @KimuraDIVP could you do an additional formal review so we have the full support of all relevant CCB members?

[ipg-jsc]

@ClemensLinnhoff have you had anything specific in mind on how to add the source field to properties that are currently a single key-value pair?

I could imagine going for @DavidJRitter904's approach in #86 and call the higher level key density_data.
For the sake of consistency I would also change elasticity → elasticity_data.

    "elasticity_data": {
        "youngs_modulus": 70e9,
        "poissons_ratio": 0.35,
        "source": "internet: https://en.wikipedia.org/wiki/Aluminium"
    },
    "density_data": {
        "density": 2699.0,
        "source": "internet: https://en.wikipedia.org/wiki/Aluminium"
    },

[ClemensLinnhoff]

@ClemensLinnhoff have you had anything specific in mind on how to add the source field to properties that are currently a single key-value pair?

I could imagine going for @DavidJRitter904's approach in #86 and call the higher level key density_data. For the sake of consistency I would also change elasticity → elasticity_data.

    "elasticity_data": {
        "youngs_modulus": 70e9,
        "poissons_ratio": 0.35,
        "source": "internet: https://en.wikipedia.org/wiki/Aluminium"
    },
    "density_data": {
        "density": 2699.0,
        "source": "internet: https://en.wikipedia.org/wiki/Aluminium"
    },

I think this is a very good solution! I originally thought about something like this:

"density": {
    "value": 2699.0,
    "source": "internet: https://en.wikipedia.org/wiki/Aluminium"
},

But I actually like your approach better.