Advanced engineering materials and components lasting longer in industrial applications under extreme conditions
Developing longer-lasting materials and components that can withstand high temperatures or thermal cycling – repeated heating and cooling that cause materials to expand and contract – is challenging. The use of less resource-intensive manufacturing technologies offers the opportunity to conserve energy and mineral resources, while also offering a new standard of efficiently producing components for engineering equipment which are resistant to high temperatures and corrosion.
Challenges hindering sustainability in hot stamping
The EU-funded HIPERMAT project focused on a use case involving a rolling beam furnace, which is used in the hot stamping process. This manufacturing process, used by the automotive industry among others, produces high volumes of lightweight components for the body-in-white structures. Yet, the furnace represents the most energy- and resource-consuming equipment in this manufacturing process. The furnace operates under challenging conditions: temperatures come close to 1 000 degrees Celsius, there are heavy loads owing to the weight of its beams, steel plates in process, and the high temperature and continuous heat inside the furnace creates a corrosive environment. These tough working conditions result in various failure modes. The frequent maintenance and component replacements for these furnaces cause significant productivity losses. They also escalate energy and resource use owing to the critical materials needed for manufacturing the furnace components.
Material innovations to address challenges in hot stamping
Seeking to make hot stamping more sustainable, HIPERMAT leveraged advanced design tools to optimise material selection and component durability. The initiative led to the development and validation of alloys resistant to high temperatures and corrosion, including variants of refractory stainless steel and other alloys applied in protective layers. “Standard refractory stainless steels encompass a wide range of standard chemical elements like carbon, nickel and chrome. By restricting the ratio of these elements in the alloy and intelligently combining others like niobium, tungsten and molybdenum, the alloy microstructure is altered, enhancing their wear and high-temperature properties,” explains project coordinator Fernando Santos.
Advanced manufacturing techniques for higher-performance components
To manufacture end components from these high-performance alloys, the project team used advanced additive manufacturing techniques like laser metal deposition (LMD), ceramic coatings and ablation technology. “Component manufacturing of high-temperature equipment typically involves tweaking bulk materials. However, the introduction of LMD and high-velocity oxy-fuel ceramic coatings allows for the use of high-cost alloys only on the surface, with the basic alloy forming just the core of the part,” outlines Santos. “This method of repairing and restoring the external layer, rather than replacing the entire part, marks a significant advancement in resource utilisation.” Ablation technology, when used in bulk material manufacturing, modifies the heterogeneous microstructure created by traditional steel casting processes. Therefore, the resulting alloys have tinier, more evenly distributed carbides, promoting higher resistance to creep and doubling current values. Following thorough destructive and non-destructive testing evaluations, these components were integrated into a real hot stamping furnace, where their performance has been continually monitored via an advanced network of embedded sensors and data processing tools. “Conventionally, sensors are placed in the furnace walls, ceiling and floors but not near the parts being processed. The ability to print sensors via LMD and embed them in functional parts close to those being processed facilitates tighter process control and improves the quality of the final part. “HIPERMAT distinguishes itself by favouring data-driven analysis over traditional physics-based simulations. This approach generates algorithms that identify critical variables, facilitating a quicker development of new materials with advanced properties to endure harsh environments,” concludes Santos. By focusing on optimising material selection and improving manufacturing techniques, HIPERMAT advanced the development of enhanced materials with potential for substantial reductions in energy and resource consumption in industrial processes.
Keywords
HIPERMAT, alloys, hot stamping, high temperatures, corrosion, ceramic coatings, ablation, laser metal deposition, data-driven analysis, physics-based simulations, process industries, energy-intensive industries
