2025-010 Update on AFS Project for Digitizing Various Knowledge Platforms—American Metalcasting Consortium (AMC)
This presentation will focus on AFS’s efforts to improve digital accessibility and operability of its various knowledge platforms. This digitization entails improving navigation and functionality/searchability between various platforms including the digital library, AFS Onlive webinars, a new, in-progress digital publication platform, CADS (Casting Alloy Database Search), and others. These efforts will also make AFS platforms more mobile-friendly and include creating new reference instructional/educational videos. Ultimately, it will highlight the various exciting ambitions with projected timelines and the status of the ongoing AMC Emergent Metal Casting Solutions (EMCS) project, funded by the Defense Logistics Agency (DLA) and AFS under the project title “Virtual Knowledge Transfer Platforms for Improved Access to Metalcasting Best Practices.”

2025-020 Bio-based Foam Patterns for Lost Foam Casting—AFS Research Project: 22-23#04: Bio-based Polymer Foam Pattern for Lost Foam Casting

The lost foam casting process has used expanded polystyrene (EPS) as the pattern material since the inception of the process. EPS is derived from petroleum distillation which carries a heavy carbon footprint and health concerns from the decomposition products during casting. A novel molding bead technology has emerged that derives a polylactic acid (PLA) foam molding bead from sustainable domestic biological sources. Bio-based foam patterns were evaluated for their potential to replace EPS as a lost foam pattern material using laboratory testing and casting trials. The lab results showed the bio-based materials didn’t produce hazardous air pollutants (HAPS) nor carcinogens. The casting trials successfully produced lost foam castings in both aluminum and gray cast iron without any modifications to the lost foam casting process.

2025-034 Advanced AM & 3D Printed Sand Mold Technologies to Support Casting Supply—America Makes (AM)

U.S. casting supply has limited responsiveness for many high integrity hardware especially for sporadic low-quantity demand military applications. Additive manufacturing provides an opportunity to augment the casting supply chain by filling gaps in supplier readiness. This presentation will discuss new advanced AM technologies that can be leveraged by the casting supply chain to improve their responsiveness to new casting orders, especially those of low-demand high-integrity hardware. 

Technologies discussed will include:
•    Improvements to 3D printed sand mold production methods for producing sand castings. 
•    Improving sand mold surface roughness, reducing outgassing from 3D printed sand mold during casting and methods to reduce dimensional variation between repetitive mold builds. 
•    AM technologies available to build rapid tooling including machining fixtures and inspection tooling will be discussed. 
•    Advanced AM high-strength metallic and polymeric systems will be presented that can be leveraged for tooling and other applications. 

In summary, this session will help the casting industry practitioner review and possibly leverage additive manufacturing technologies to support their particular casting processes and applications. 

2025-055 The Effect of Various In-Mold Additions on the Austenite Grain Morphology and the Eutectic Cell Size of a Hypoeutectic Gray Cast Iron—AFS Funded Project: 22-23#01: Refining Austenite in Gray Irons

This work is a study of the effects that different in-mold additions have on the morphology of austenite and the eutectic cell structure in grey iron. The experiment utilizes a novel heat-treatment process that revealed the grain boundaries of austenite at room temperature in low-alloy cast iron. The in-mold additions studied were Al, Ca, Ce (mischmetal), Sr, and Ti. Each was poured during the same heat of a hypoeutectic grey iron with a high-purity silicon in-ladle addition. The austenite grain boundaries and the eutectic cell structure were revealed successfully. The results indicated that the Al addition sample had the least refined structure of austenite, and the Sr sample has the most refined austenite. Additionally, there is evidence to suggest a correlation between a larger equiaxed zone size and larger eutectic cells in the equiaxed zone.

2025-061 Benchmarking Shell Recycling, Productivity Metrics, and Risering Practices in the North American Investment Casting Industry—American Metalcasting Consortium (AMC)

This paper documents the results of a recent survey of the domestic investment casting industry. It was conducted in support of a research project co-sponsored by the project team and by the Defense Logistics Agency-Troop Support, Philadelphia, Pennsylvania, and the Defense Logistics agency Information Operations, J68, Research and Development, Ft. Belvoir, Virginia. The 26-question survey shed light on prevalent industry practices related to risering castings, shell and casting productivity, and the use/opportunity for recycling investment casting shells. The results largely confirmed the research team’s observations of the industry and provided metric references for the various opportunities involved in developing improved risering tools/technologies specific to investment castings, recycling shells, and improving productivity in shell production.

2025-067 Effect of Ceramic Aggregate on Cast Iron Mechanical Properties—AFS Funded Project: 19-20#02: Effect of Ceramic Sand on Cast Iron Mechanical Properties

Because of the recently-passed OSHA Silica Rule, many iron foundries have or are considering changing from silica sand to a ceramic aggregate to alleviate the issue. The AFS Cast Iron Division initiated a research project to understand the impact of the change in the microstructure and associated mechanical properties on cast iron that might accompany the use of these ceramic molding media. 

Funded by AFS, a research project was performed to assess the mechanical properties of class 40 gray iron and 80-55-06 ductile iron castings using an experimental casting matrix of the three aggregates with two sand-to-metal ratios. Results indicated that ceramic aggregates have a noticeable influence on mechanical properties of gray and ductile iron but sand-to metal-ratio has an influence on the degree of properties variation.

2025-074 Development of a Self-regulating Permanent Mold incorporating Phase Change Materials (PCMs—Advanced Casting Research Center (ACRC)

Dynamic casting processes such as permanent mold and die casting require the effective thermal management of molds to balance rapid heat absorption from the molten metal and immediate heat recovery to the mold for subsequent casting cycles. Existing thermal technologies like direct flame and coolants have difficulty controlling heat transfer, resulting in thermomechanical fatigue of the mold due to excessive heating and cooling. Controlling the heat transfer in molds is paramount to ensuring the production of high-quality castings and reducing production cycle times. 

An innovative approach to controlling thermal gradients in molds involves incorporating phase change materials (PCMs) inside the molds. With their thermal energy storage capability and high latent heat, PCMs embedded in molds facilitate mold temperature self-regulation for heating and cooling as the PCM undergoes solid-liquid phase transformations during the casting process. In this paper, the feasibility and applicability of PCMs in dynamic casting processes will be discussed.

2025-089 Understanding the Effects of Boron on the Microstructure and Mechanical Properties of Pearlitic Ductile Iron—AFS Funded Research: 22-23#06: Understanding and Mitigating the Effect of Boron in Ductile Iron

Trace quantities of boron affect the microstructure and mechanical properties of spheroidal graphite irons (SGI). To quantify these effects, a pearlitic SGI with controlled boron residuals from 12 to 96 ppm was cast into nobake silica molds featuring step blocks with 5, 15, 30, and 50 mm thicknesses, chill wedges, and integrated thermal analysis cups. Tensile properties were determined via modified Keel blocks. Solidification simulations predicted cooling rates of resulting castings. Boron additions up to 39 ppm decreased the tensile and yield strengths of the alloy, as well as reduced the pearlite fraction and hardness for all section thicknesses. Additions up to 39 ppm decreased the temperature at the end of solidification and raised eutectoid temperatures of interest. The interacting effects of boron and cooling rate were prominent in the 5 mm section, displaying increased ferrite content, nodule number density, and decreased nodularity at all levels of boron.

2025-128 Progress and Problems In the Production of Nano-Reinforced Aluminum Alloys—American Metalcasting Consortium (AMC)

The production of aluminum nanocomposites with conventional and experimental aluminum alloys reinforced with nano-sized alumina using a master alloy is discussed. The reinforcement phase can have both positive and negative interactions with various alloying elements in both the liquid matrix and the solid master alloy. Magnesium is usually bound to the particles, reducing the amount available for solid-solution strengthening or as mixed precipitates. On the other hand, certain elements (Mg, Ce) are highly reactive, aiding in the dispersion of the master, reducing the surface tension of the matrix alloy (Mg, Zr, Ni, Ce), or producing exothermic reactions during mixing (Ce,Zr,Cu2O, CuO), which also aids in master alloy dispersion.

2025-129 Quantifying Process Relationships for Surface Defects on Chemically Bonded Sand Systems—American Metalcasting Consortium (AMC)

This presentation will provide an update on the current research into the causes of casting surface defects. Current progress on both defect scanning technologies and classification will be presented. Future efforts in determining process variable effects on defects in aluminum castings will also be discussed.

2025-130 Industry Best Practice Data Driven Design Allowable Properties for Some Common Alloys in CADS (Casting Alloy Data Search) Online Tool—American Metalcasting Consortium (AMC)

This DLA-funded and AMC/AFS-managed research project has led to the development of a web-based casting alloy data search tool for the design and simulation engineers, which provide engineering properties and in most cases fatigue with the supporting pedigreed data, such as chemistry, mold material, casting process, section thickness, type of test bar and heat treatment, etc., in contrast to the typical handbook static data with no or little supporting pedigree information. 

Improved data will enable better casting part designs capable of delivering a collection of long-term objectives, i.e., longer service life, lower scrap, lighter weight, and better performance. Through CADS, AFS provides current and qualified information generated using the latest methods and disseminates this information in a user-friendly format to both users and manufacturers of castings. 
Our latest effort will be presented and will be focused on developing industry best-practice-data driven design allowable property values using standard MMPDS methods for 24 new alloys (two copper-base, four aluminum-base, six iron-base, and twelve steel-base grades) from over 11 foundries. The AFS foundry members provided the data and PDA LLC performed the data analysis using the MMPDS-established statistical method, which takes into account the heat and lot variability from the same foundry as well as from one foundry to another foundry for the same alloy grade.

2025-140 Investment Casting Agility and Sustainability Research—American Metalcasting Consortium (AMC)

This five-year research program focusses on reducing shell-drying cycle time and smart-pattern burn out algorithm; recycling and reusing alumino-silicate investment shells and better understanding feeding behavior of investment cast steels by establishing feeding distances and risering guide. We will present the progress made since the start of the project in October 2023 with some preliminary results to share and outline the investment foundry participation into this on-going project.

2025-145 Machinability of Solution Strengthened Ferritic Ductile Iron—AFS Funded Research 20-21#06: Machinability of Solution Strengthened Ferritic Ductile Iron

Solution-strengthened ferritic ductile iron is a grade of ductile iron where the ferritic matrix is solution-strengthened by silicon. The addition of silicon results in a combination of higher mechanical properties and higher elongations as compared to standard grades of ferritic ductile iron. Some research suggests silicon solution-strengthened ferritic ductile iron (SSFDI) grades can result in a 10–50% machining cost savings compared to conventional grades. Although these grades can result in lower machining costs, some grades have an increased base cost in the raw material form. For example, 500-14 SSFDI and 600-10 SSFDI ductile iron grades can be 1%–4% higher in base casting costs over comparable conventional grades. The lack of machining knowledge has impeded the growth of 500-14 SSFDI and 600-10 SSFDI in North American markets due to machining costs being kept at conventional grade speeds and feeds.

2025-147 Effects of Silicon in High-Cr White Cast Irons—AFS Funded Project: 22-23#03: Effect of Si in High-Cr White Cast Irons

To improve their performance, this research characterized the effects of Si on eutectic saturation, the ideal hardening temperature, hardenability, carbide fraction, and alloying element content in the constituents of high-Cr white cast irons. The influence of Si on % eutectic saturation was not clear. When analyzing carbide fraction, Si had a negligible effect in the 15% Cr series, but seemed to cause the 25% Cr series to develop less eutectic carbide, that is, become more hypoeutectic. Cr was richest in the eutectic carbides and leanest in the eutectic austenite matrix. Si was largely rejected from the eutectic carbides and richest in the eutectic austenite.