“Brushes” is a tool that can help you in almost any graphic software. Even if the software doesn’t have brush capability, per se, you can still use the shapes in the program.
How to import .abr files
Press over three horizontal dots on the top right corner of the Brush panel, and select Add new folder.
(Or press plus symbol).
Inside that folder, press plus symbol
Select the option open texture file, select .abr file.
Convert .abr file format to .png
However, the Photoshop format, *.ABR, is not compatible with other programs and are therefore unusable.
Now, with abrViewer you can export them to *.PNG format and make them useful in a number of ways.
Follow this steps to convert abr files to png:
http://www.wikihow.com/Convert-Photoshop-Brushes-with-abrViewer
Link to ABR_VIEWER download http://sourceforge.net/projects/abrviewer/files/abrViewer.NET2_2.0/abrViewer.rel.NET2_2.0/
Once converted import .png alphas on 3DCoat. You can drag and drop the file to the viewport, and a popup dialog with import options shows up.