The modulus of elasticity is in general temperature dependent. For stainless steel at room temperature, i.e. 20°C, the modulus of elasticity lies in the range 190 - 210 GPa (10^9 Pa). A good estimate for a generic steel may well be a value of 200 GPa. Otherwise, you have to look for the mechanical properties based on the grade of the steel you are working with. Properties for specific stainless steels can be found for example at

 http://www.aerospacemetals.com/stainless-steel-distributor.html (a producer)

http://www.nist.gov/data/PDFfiles/jpcrd34.pdf (US NIST)

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