methods and apparatus for manufacturing strengthened ceramic honeycomb articles having thickened peripheral web segments by extruding , drying and firing honeycomb shapes formed by the extrusion of plasticized ceramic powder batches through honeycomb extrusion dies having peripheral slots incorporating outer widened slot portions of controlled depths , the controlled depths being selected to increase ceramic powder batch flow through the peripheral slots to a degree sufficient to form the thickened web segments but insufficient to cause geometric distortion of the thickened web segments .