Influence of nodule count on residual stresses and distortion in thin wall ductile iron plates of different matrices

摘要: Abstract Surface characteristics of thin wall ductile iron (TWDI) parts, such as residual stresses, distortion and dimensional changes produced during casting heat treatment, are relevant variables when it comes to production processes design. This work focuses on the effect nodule count stresses (RS) TWDI plates distortion. As-cast, ferritised austempered samples were employed. The role played by two typical austempering temperatures (280 360 °C) three significantly different counts (265, 1200 1700 nodules (nod)/mm 2 ) discussed establishing microstructural changes, i.e., microstructure fineness, retained austenite volume fraction ( V γ %), carbon content C %). Besides, profiles below surface determined. Results show that all display compressive RS neighbouring layers. Samples with high at 280 °C lead higher well an increase in field surface. As-cast exhibit noticeably lower values.