A parametric life cycle assessment model for ductile cast iron components

• Designed a life cycle parametric model for ductile iron casting and design decisions. • Generated representative foundry data using measurements from 26% of the US industry. • Identified key manufacturing and design decisions using Sobol Indices analysis. • Compared life cycle environmental impacts of ductile iron castings with other materials. • Model showed major opportunities to improve casting yields and furnace efficiencies. Life cycle assessment (LCA) is widely used to evaluate product environmental impacts, while detailed LCAs are missing that model the effect of design and manufacturing decisions on U.S. ductile iron casting environmental impacts. We develop a parametric LCA model by collecting inventory data from 11 foundries (26% of U.S. production) and literature to quantify the impact of design and manufacturing decisions on the product's cumulative energy demand (CED) and global warming potential (GWP). The model reveals the cradle-to-gate CED and GWP of U.S. ductile iron products at 24–50 MJ/kg product (mean: 37 MJ/kg product ) and 1.6–3.0 kg.CO 2eq ./kg product (mean: 2.2 kg.CO 2eq ./kg product ). A Sobol-indices sensitivity analysis revealed the factors that have the greatest effect in reducing these environmental impacts: casting yield, electricity grid, recycled content, and furnace technology. A comparative whole life cycle analysis of automotive ductile iron applications versus forged steel, stamped steel and aluminum alternatives highlights the design and manufacturing conditions that minimize life cycle impacts.