Iknow there are small sized tensile bar standards.. but I dont think this is what you're asking for...
Really depending on what you're working with there must be standards (IEEE?, MIL?, even ASTM) for testing your electronic parts.
If you cant find a standard then:
Which way do you need to test the strength? each different strength must be tested in the proper way. Likely you will need to design mounting apparatus to attach your sample to the testing machine.
then its as simple as loading to yeild, then failure while taking a good record of the data (applied load, deflection, elongation, etc...)
nick