As all we know about SitePages Library in SharePoint. This Library contains both wiki and webpart pages. We can able to export and import this library using powershell script. Here is the powershell script to export library
Export-SPWeb -Identity "http://yoursiteurl" -ItemUrl "/LibraryName" -Path "c:\temp"
Import-SPWeb -Identity "http://yoursiteUrl" -Path "C:\temp\filename.cmp"
Export-SPWeb -Identity "http://yoursiteurl" -ItemUrl "/LibraryName" -Path "c:\temp"
Import-SPWeb -Identity "http://yoursiteUrl" -Path "C:\temp\filename.cmp"