Effect of Chemistry and Section Size On Properties of Ductile Iron 520243
THIS paper presents the results of investigations conducted at the University of Michigan under the sponsorship of the International Nickel Co., Inc., to determine the influence of carbon, silicon, and phosphorus contents and of section size on the mechanical properties of ductile cast iron.
Carbon contents in the range of 2.75% to 4.10% had a minor controlling influence on the mechanical properties. Silicon, through its influence on the matrix structure and its solid solution hardening effect, exerts a major effect on the mechanical properties.
Increasing the silicon content from 0.1% to 5.0% produces linear increases in tensile and yield stregnths and hardness and decreases in ductility. Increasing the phosphorus content from 0.04 to 0.40% increases hardness and decreases ductility.
Ductile iron exhibits moderate section sensitivity, either in the as-cast or fully annealed conditions. With increasing section thickness the properties are all lowered slightly.