| 摘要 |
PURPOSE:To heighten the corrosion resistance of a steel cord and the durability of a pneumatic tire, by causing nitrogen to diffuse into the surface of the steel cord and by using the steel cord to reinforce the carcass and reinforcing belt layer of the tire. CONSTITUTION:At least one of the carcass and belt layer of a pneumatic tire is reinforced by a steel cord whose surface if treated by causing nitrogen to diffuse into the surface. The carbon content of the steel cord is 0.65 to 0.85% by weight. the quantity of the nitrogen caused to diffuse into the surface of the cord is 1.0 to 2.5% by weight, on the average, to the depth of 0.5mu from the surface. As a result, the performance of the tire is prevented from deteriorating and the corrosion fatigue resistance of the steel cord and the durability of the tire are much heightened. |
