| 摘要 |
PURPOSE:To manufacture the titled parts without carrying out isothermal transformation by heat-treating an alloy cast iron material having the composition of acicular cast iron to convert the matrix structure into granular pearlite, mechanically working the material, and heat-treating it again to convert the granular pealite into uniform bainite. CONSTITUTION:A material consiting of, by weight, 0.5-2.0% Cu, 1.0-2.0% Mo, 1.0-3.0% Ni and the balance cast iron is heated, held at 800-1,000 deg.C for 0.5- 6.0hr, and allowed to cool in the air. It is heated again, held at 670-760 deg.C for 0.5-6.0hr, and allowed to cool in the air or furnace-cooled. The material heat- treated as mentioned above so as to condition the structure is mechanically worked to the shape of a product. The worked material is heated to 800- 1,000 deg.C to austenitize the matrix structure, and it is allowed to cool in the air to convert the austenite into bainite. Thus, a cast iron product with both high workability (toughness) and wear resistance is manufactured. |
