Casting Solutions for Readiness

• Image Analysis for Digital Radiographs, University of Alabama at Birmingham – Robin Foley, John Griffin, William Monroe
  • UAB is developing a semi-automated image analysis tool to identify and mark digital radiography indications. This will serve as the baseline tool for development of a tool that would be capable of rating digital radiographs and verify relationship between mechanical properties and maximum indication length. This maximum indication length will be determined using the radiography test (RT) standard developed by University of Iowa.

Innovative Casting Technologies

• Digital Surface Inspection, Iowa State University – Frank Peters
  • Current standards for inspection of cast metal surfaces use qualitative methods leaving room for variation in interpretation of the standard. Standards used in the metal casting industry are the Alloy Casting Institute (ACI) Surface Indicator Scale, Manufacturer Standardization Society (MSS) SP-55 Visual Method, and American Society for Testing and Materials (ASTM) A802 that reference the Steel Castings Research and Trade Association (SCRATA) comparator plates. Some surface roughness inspection processes use the GAR Electroforming Cast Comparator C9. Other standards include ISO 11971 and BS EN 1370, which overviews SCRATA and BNIF, and ASTM A997 for investment castings. Digitizing the process will make the inspection more repeatable and reproducible and will help avoid confusion between the foundries and their customers. This will also help foundries verify visual inspection results internally or promote automation of the inspection qualification process. A quantitative visual inspection method with improved gage R&R could be leveraged to evaluate the effect of surface conditions on product performance.
• Heavy Section Austenitic Stainless Steels, Lehigh University – John DuPont
  • Heat resistant austenitic stainless steels are capable of operating at high temperatures and are used in various applications. Depending on composition and section size (cooling rate), it can be difficult to achieve acceptable tensile properties in HH grade. The HK and HP grades are susceptible to cracking during welding and riser removal that has been attributed to carbide formation. This project will investigate the influence of composition on the formation of carbides, its type and morphology and their effects on mechanical properties and cracking susceptibility of these alloys. A neural network model will be developed that establishes the relationship between chemistry, microstructure, and tensile properties. This predictive capability will allow optimization of mechanical properties and improvement of manufacturability.
• Intensive Quenching, Missouri University of Science and Technology – Laura Bartlett
  • Intensive quenching has been utilized in industrial settings to improve the formation of martensitic microstructures and improve the fatigue performance of steel. An additional benefit of intensive quenching is the elimination of size limitations from the dimensions of traditional quench tanks. Traditional methods of quenching also create the potential for quench cracking as a result of the compressive forces the steel is subjected to upon cooling. While intensive quenching is not a new technology, the goal of this project is to determine if intensive quenching is beneficial or detrimental to castings given possible inclusions, porosity, or surface roughness that may be present in castings and have the potential to act as stress risers.
• Cost Modeling, University of Alabama – Charles Monroe
  • The ability to produce and deliver cast parts on time and with the required quality is thwarted by unexpected process complexities and associated manufacturing difficulties. A cost modeling software will be developed to predict process complexity and estimate variable costs. This project will identify possible manufacturing routes, improve the speed, quality, and predictability of production, and minimize the operation and sustainment costs through better reliability of replacement parts.
• Modeling of Reoxidation Inclusions in Steel Castings, University of Iowa – Christoph Beckermann and Richard Hardin
  • Steel cleanliness still remains a major challenge in the steel industry. It was found that reoxidation inclusions are the major source of these inclusions. Reoxidation is the reaction of elements in liquid steel with oxygen after the molten steel has been deoxidized. Air entrainment during pouring is the main cause of reoxidation inclusions. SFSA’s Clean Steel program during the 1980’s and 1990’s has investigated the factors that affect air entrainment by conducting water modeling and several casting trials. University of Iowa (UI) is now developing a computational modeling tool that would predict the amount of air entrained during pouring and inclusion formation in steel castings. This modeling tool would help design and evaluate gating systems of steel castings.
• Rapid Production Using Additive Manufacturing, University of Northern Iowa – Jerry Thiel
  • Rapid response and more suppliers are needed in the replacement of critical cast components for legacy weapons systems. Tooling including patterns and core boxes are often difficult to locate. New tooling for manufacturing cast metal parts is often expensive and requires significant lead-times. This project will enhance the use of AM in steel foundries by identifying the barriers and challenges with adoption of AM technologies. This project will also enhance the use of AM by improving surface finish of 3D printed sand mold castings and by developing 3D printing process for investment casting shells.
• Workforce Development and Specifications Toolkit, SFSA
  • The steel casting industry has identified workforce development and customer education as key strategic initiatives. The objective of this project is to develop and maintain online tools that provide the essential skills and knowledge training to the next generation workforce, specification support to casting buyers and manufacturers, and to facilitate the transition of current and emerging steel technology development to Government and industry. Webinars on an extensive range of topics for foundry employees and for casting users will be presented. A web-based specification tool will also be developed and made available on the SFSA website where anyone can search and cross reference steel casting specifications or different steel grades.