Example Overall thermoelastic response of a multilayer

Mo layer so that any extensional strain which tends to develop along the interface in the AI2O3 layer during any temperature change AT is compensated by an equal strain in the multilayer film (b) Assuming that the entire multilayer is stress-free at room temperature, what is the stress state in each layer when the laminate is subjected to a temperature increase of 40°C  

The layer geometry is such that there is no stress in the AI2O3 layer. 

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