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The application of titanium components is generally limited by their high raw material and manufacturing costs. In this paper, a lower cost cast titanium alloy based on the Ti-Al-Fe system has been designed using an ICME approach. The new alloy Ti-6Al-5Fe-0.05B-0.05C (all wt.%) significantly reduces raw material cost and demonstrates improved castability compared with the baseline Ti-6Al-4V alloy. The fine primary and secondary α phase microstructure in the new alloy, due to Fe partitioning, provides exceptionally high strength (1023 MPa yield strength and 1136 MPa ultimate tensile strength) and reasonable ductility (3.7% elongation) for structural applications. On the manufacturing front, the high cost multi-step investment casting process currently used can now be replaced with a low-cost permanent mold casting process using steel molds and a novel ceramic coating. An experimental casting setup, including an induction skull melting (ISM) system, a gravity tilt-pour system and a ceramic-coated H13 steel mold, has been used to produce near-net-shape permanent metallic mold castings with the new titanium alloy developed. Using this setup, and aided by casting process simulation, a prototype automotive connecting rod was cast successfully. The ZrO2 ceramic coating applied to the H13 steel mold was proven effective in minimizing the metal-mold reactions.

Lightweighting is a well-known strategy for increasing energy efficiency and reducing greenhouse gas emissions. Magnesium, the lightest structural metal, will thus see increased use in a wide range of structural [...]

A206 aluminum alloy is an important Al‐cast alloy with high mechanical strength. However, its dependence on θ′‐phase for effective strengthening raises concern for its anti‐corrosion performance in service. This paper systematically studies nano‐treating A206 with TiC nanoparticles to investigate its effects on overall corrosion behavior. Immersion tests and electrochemical measurements have been used to understand the nano‐treating contributions to the improved corrosion resistance of A206 under T4 and T6 heat treatment. The results indicate that the pseudo‐dispersion of TiC at or near the grain boundary (GB) and precipitates strengthens the GBs, and more rapid passivation near the TiC‐dense zone introduces a more uniform corrosion feature. The uniform corrosion with rapid passivation greatly facilitates the corrosion control of nano‐treated A206 under T4 and T6 heat treatment, allowing supreme anti‐corrosion stability for high‐strength A206 alloy. [ABSTRACT FROM AUTHOR]