抄録
This paper proposes a new pipe-bulging process utilizing a lost core of fiber-reinforced ice. The process is as follows. First, the cavity of the pipe, or channel material, is filled with fiber-reinforced ice, known as the lost core. Second, the pipe is longitudinally compressed as a composite billet, and extruded in the lateral direction. After deformation, the lost core is melted and removed. Low temperature melting alloys are conventionally utilized for the lost core in such processes; however, these alloys usually contain Pb (e.g., Bi-Pb-Sn-In or Pb-Cd system alloys) or are expensive (e.g, In-Sn system alloys). The authors utilize an ice core reinforced with fiber of recycled paper pulp instead of the above alloys for less expensive and more environmentally conscious processes.