Current progress and development trends of low-cost titanium alloys

Titanium alloys， owing to their high specific strength， excellent toughness， and outstanding corrosion resistance， are widely used in aerospace， defense， marine engineering， and medical applications. However， their high production cost remains a major barrier to large-scale adoption. This review summarizes the current research status and future development trends of low-cost titanium alloys， with a focus on both conventional design strategies and emerging technological pathways. In conventional approaches， the replacement of expensive alloying elements （e.g.， Mo，V） with more economical alternatives （e.g.， Fe， Cr， O， N）， combined with optimized melting techniques and processing routes， has significantly reduced material costs. In terms of emerging technologies， high-throughput diffusion techniques， machine learning， and transformation-induced plasticity/twinning-induced plasticity （TRIP/TWIP） mechanisms provide a crucial theoretical foundation for the rapid development of high-performance， low-cost titanium alloys that can be fabricated via short-process routes.Near-net-shape forming techniques， with their high material utilization and short processing cycles， have become key tools for cost control.Looking forward， integrating TRIP/TWIP-based alloy design with advanced processing and manufacturing techniques， along with the strategic optimization of interstitial elements （e.g.， O， N）， is expected to further reduce production costs. Such progress will accelerate the large-scale application of titanium alloys in fields such as automotive light-weighting and military armor， ultimately promoting their widespread adoption across multiple industries.