cast iron can be modified through the manufacturing process to optimize its mechanical and physical properties, such as strength and durability. This property makes it a material of choice for use in the transportation and machinery industries, which rely on cast iron’s resistance to wear, deformation, and rusting to design high-performance bridges, tools, and engine parts. But the manufacturing process is as much art as science, producing good results yet not capturing cast iron’s full potential. Controversy still exists over the correlation between manufacturing casting parameters and desirable properties. Limited by typical industrial 2-D imaging techniques or time-consuming 3-D laboratory studies, researchers have been unable to pinpoint the exact processing parameters needed to elicit the ideal properties for each cast iron application. Finding an easier way to peer deep inside the alloy to get a definitive answer could be a boon for consumers as well as give the U.S. industry a competitive advantage.
According to a study released in the journal Scripta Materialia, high-energy synchrotron X-rays can provide that insight. By understanding the structure, it will be possible to develop alloys with improved mechanical and thermal properties. This implies that for applications such as vehicle engine and engine components, one could use less material and reduce overall vehicle weight. For the transportation industry, the ability to modify manufacturing processes to create high-performance materials could aid in the development of more fuel-efficient engines or engine parts that can withstand heat better to have longer lifespans. The study results showed that high-energy X-ray tomography can reveal previously unknown behaviors of graphite in cast iron, such as the growth of nodules, as it undergoes various treatments. The X-rays can also unambiguously classify the particle type involved in the behavior, which is critical to identifying the structure-process relationship. These insights hold the key to manipulating the atomic structure of the graphite through manufacturing treatments such as changing the chemistry of the melt and altering the inoculants added to the liquid cast iron.