| 摘要 |
PURPOSE:To produce an inexpensive bicycle rim having excellent corrosion resistance by using a ferritic stainless steel which contains C and N at low ratios and contains Ti or Nb as an element for stabilizing said elements as the bicycle rim material and subjecting the same to a heat treatment and forming under specific conditions. CONSTITUTION:The ferritic stainless steel which contains, by weight %, <0.030% C, <0.030% N, 1 or 2 kinds of Ti and Nb as the element for stabiliz ing the C and N at 4-20 times the total content of the C and N, and further <2.0% Mo and having 10-26% content of Cr is used as the material for the bicycle rim. After this ingot is hot rolled, the hot rolled sheet is pickled and descaled and is further cold rolled to the sheet material having the final objec tive thickness; thereafter, the sheet is subjected to finish annealing for short time of 10min at 750-950 deg.C in a reducing atmosphere having 10--40 deg.C dew point and consisting of 1-30vol% H2 and the balance N2. The sheet is then worked to the rim in the as-annealed state of the surface. The bicycle rim having excellent ductility, toughness and corrosion resistance is produced at a low cost. |
