How to merge the faces of 2 surface components under certain distance? (geometry files attached)

Hi all,

I have 2 components imported from 2 .stl files. And now 2 surfaces with many egdes have been generated from stl mesh. As we can see from the image below, in the up-right corner, some part the geometry was masked to show inner part of the geometry. And the 2 surface are crossing with each other, because physically they should share same boundary in that area.

I need to make the two geometry (red and blue)in the up-right corner part share same boundary. So I can generate the surfacemesh, and they can share the same elements on that boundary. Is there any way to merge the boundaries of 2 geometries when they are very close? Thank you.

Ke

Download:

Used version: Hypermesh 2017