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Myers, Jim

Publications and source records attributed to Myers, Jim.

Cast Alumina-Forming Austenitic Stainless Steels for High Temperature Heat Treatment Furnace Rolls

Alloy developers worldwide have struggled to create creep-resistant alumina-forming, iron-based austenitic stainless steels for use as high-temperature structural alloys, but with limited success in balancing alloy cost, oxidation, and creep resistance. Here, this article describes the research and development of a novel cast alumina-forming austenitic stainless steel. This work won the prestigious Engineering Materials Achievement Award presented at IMAT 2023 in Detroit.

36 MATERIALS SCIENCE↗

Cast Components for High Temperature Concentrated Solar Power Thermal Systems

Concentrating Solar-Thermal Power (CSP) components such as piping, valves fittings are required for use at temperatures up to 800°C. These are anticipated to be made using Nickel-based alloys such as Haynes ® 230 ® , Haynes ® 282 ® , or IN ® 740H ® and can contribute significantly to the cost of a CSP Gen 3 plant. Thus, there is a significant motivation to lower the cost of materials and components so that the capital costs can be minimized. In all these cases, the cost of the component has two contributions: 1. Materials cost, and 2. Manufacturing cost. Both materials cost and manufacturing costs must be kept low to attain the lowest possible cost. Materials cost can be lowered by using materials that have the ideal combination of properties at the lowest cost. Another avenue to lower cost is chose a manufacturing process that has the potential to lower the cost. Traditionally tubes are made from billets through a wrought process and can be expensive. An alternative process to consider is the centrifugal casting process where the tube is directly fabricated from molten metal. In this case, the molten metal is poured inside a cylindrical metallic mold with an insulating layer and is spun rapidly. A wide range of sizes (diameter, wall thickness, and length) can be cast using this process. The objective of this project was to develop the process for fabricating pipes and related components using a centrifugal casting process and to measure the properties of alloys fabricated using this process.

14 SOLAR ENERGY↗

Development of Cast Valve Bodies For High Temperature Service

Gen 3 Concentrating Solar-Thermal Power (CSP) system components are required to operate at 750°C - 800°C to achieve the Sunshot target of 6 cents/kWh. Haynes ® 282 and IN ® 740H are preferred alloys for the construction of these components due to their high tensile and creep strengths for service at temperatures greater than 750°C. There is significant motivation to lower the cost of materials and components so that the capital costs can be minimized. One approach to reduce costs is to fabricate castings at the lowest possible cost. To obtain the lowest cost in castings, there is a significant need to maximize yields in castings by decreasing rejects due to casting defects and to minimize wastage in material lost in the gating systems. However, very little work has been performed to develop cast products using Haynes ® 282. Although preliminary work has established the feasibility of casting Haynes ® 282 using investment and sand casting, there are no commercial cast components available. In particular, there is significant interest in the development of casting design and process technology for the fabrication of components such as valve bodies using Haynes ® 282.

14 SOLAR ENERGY↗