The case for physical experiments in a digital age

Abstract

Casting and solidification simulations, heat transfer models, hot isostatic press consolidation simulations, hot working simulations, phase equilibrium calculations… the list is quite long of digital technologies embraced by ATI and other producers of specialty materials and components. Through virtual experimentation, product development cycle time and cost is reduced, the potential impact of process upsets can be determined without testing, and sensitivity to process variation can be assessed prior to ever making any metal, among other efficiency and cost benefits. Nevertheless, effective, efficient development of superalloys manufacturing processes requires that these digital experiments are complemented by careful physical experiments at the pilot scale in order to manage risk and expense of scale-up. Pilot scale development provides critical insight into factors not easily computed, such as the integrity of a VIM cast electrode, the variation in segregation during VAR melting, and cracking due to grain structure or surface condition during hot working. ATI integrates use of physical experiments conducted in pilot research facilities and computational methods to facilitate both new product development and development of the manufacturing method. Such an approach has been instrumental in the development of ATI 718Plus®alloy and René 65 alloy and an array of new products including cast-and-wrought, powder, and titanium alloys and components. This paper will discuss the advantages of using physical experiments to streamline the development of new products and manufacturing methods and some of the ways ATI capitalizes on the combined approach