BoundaryMesh

BoundaryMesh[mreg] gives a BoundaryMeshRegion from a MeshRegion mreg.

Examples

Create boundary mesh from region:

mesh = MeshRegion[{{0, 0}, {1, 0}, {1, 1}, {0, 1}}, Polygon[{1, 2, 3, 4}]];
BoundaryMesh[mesh]

Please visit the official Wolfram Language Reference for more details.