Titanium’s exceptional strength-to-weight ratio and corrosion resistance make it critical in aerospace, biomedical, and energy industries, yet its production is energy-intensive and environmentally challenging due to complex processing steps. This study investigates the environmental performance of an innovative recycling route that enables the production of solid Ti6Al4V components directly from machining chips through integrated sintering and forging steps. The assessment, conducted using the Environmental Footprint, Cumulative Energy Demand, and IPCC Global Warming Potential methods, reveals a substantial 85.8% reduction in overall environmental impact compared to conventional manufacturing, largely attributed to the elimination of titanium sponge production. The process requires 75.9 MJ of energy and emits 3.1 kg CO2-eq per kilogram of finished part, with the sintering step identified as the primary hotspot, driven mainly by electricity consumption and its effect on the ‘Fossil resource use’ category. Scenario modeling indicates that reducing the dwell time at 1200 °C from 30 min to 5 min decreases density slightly (from 99.9% to 99.8%) while lowering environmental impact by 23.5%. In contrast, decreasing the sintering temperature to 950 °C (30 min dwell) reduces density to 99.3% but achieves only a 4.8% impact reduction. A hypothetical shift to a cleaner electricity mix with 36% more renewables further reduces overall impacts by 20.8%, reinforcing the process’s potential as a sustainable alternative for titanium manufacturing.
Hosseini et al. (Thu,) studied this question.