fixed sab on void materials
fixed sab on void materials

paulromano/openmc,sxds/opemmc,walshjon/openmc,walshjon/openmc,shenqicang/openmc,bhermanmit/openmc,johnnyliu27/openmc,shenqicang/openmc,liangjg/openmc,johnnyliu27/openmc,samuelshaner/openmc,shikhar413/openmc,sxds/opemmc,samuelshaner/openmc,amandalund/openmc,smharper/openmc,amandalund/openmc,liangjg/openmc,paulromano/openmc,johnnyliu27/openmc,samuelshaner/openmc,wbinventor/openmc,smharper/openmc,mit-crpg/openmc,nhorelik/openmc,shikhar413/openmc,kellyrowland/openmc,lilulu/openmc,mjlong/openmc,wbinventor/openmc,shikhar413/openmc,amandalund/openmc,liangjg/openmc,walshjon/openmc,mit-crpg/openmc,johnnyliu27/openmc,paulromano/openmc,amandalund/openmc,samuelshaner/openmc,wbinventor/openmc,liangjg/openmc,lilulu/openmc,smharper/openmc,smharper/openmc,walshjon/openmc,lilulu/openmc,mit-crpg/openmc,paulromano/openmc,bhermanmit/openmc,mjlong/openmc,wbinventor/openmc,shikhar413/openmc,mit-crpg/openmc,nhorelik/openmc,kellyrowland/openmc