Does the model consider the composition entered in the "Max Hardness" area for both the pipe and the sleeve?

The model does not currently allow for modeling two materials however a current project looking to update the model will allow this option (Hot Tap V5 will have this feature).

How we usually address the two different materials is to usually take a conservative approach by using the material with the higher CE for the input. Then it would be expected that the other material will have a lower hardness.