| 摘要 |
<p>PURPOSE:To manufacture the pipe which neither cracks nor deforms while reduced in weight by forming a compound pipe which is made large in overall thickness by using an inside material with good workability and an outside thin alloy material, and removing the inside material after boring, etc. CONSTITUTION:The compound pipe of 35mm in external diameter is formed of the inside Cu material and the outside 90% Pt, 7% Pt, and 3% Co material by extrusion and reduced by boring to a 25mm internal diameter, and then drawn; and a heat treatment is performed in an N2+H2 atmosphere at 800 deg.C for 30 minutes to form a pipe of 19.6mm in external diameter and 19.0mm in internal diameter. Then boring and annealing by a burner are carried out and then tone hole machining is performed; and an acid treatment using dilute sulfuric acid is carried out to remove the inside Cu, thus forming a projection part which has a 13.8mm external diameter, a 13.5mm internal diameter, and a 1.9mm length. This pipe is thick as the compound pipe and uses the material with good workability inside to serve as a buffer in the machining, so that the pipe which neither cracks nor deforms and is thin and excellent in outward appearance can be obtained. Further, Au-based alloy is usable as the outside material.</p> |
