2015 Volume 56 Issue 12 Pages 2092-2094
We have developed a new hole-filling technique that differs from conventional techniques, the friction hydro pillar processing (FHPP) and friction taper stud welding (FTSW), which fill holes by utilising friction welding. The new method friction welds a hole using a rotating consumable tool with a diameter larger than the hole diameter. The new method can be applied to soft alloys such as aluminium alloys and is suitable for making holes in thin sheets to disappear and is superior to FHPP and FTSW in these aspects. In addition, unlike the hole-filling method using nonconsumable tools, the new method does not reduce sheet thickness. Observations of sections of the samples created using the new method shows that the hole has disappeared because of compressive deformation. In addition, no defects were observed inside the samples. Observation of the grains demonstrated the weld line by the friction welding between the workpiece and tool, and micro-grains derived from dynamic recrystallization were observed.