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A D V A N C E D M A T E R I A L S & P R O C E S S E S | J A N U A R Y 2 0 2 1 8 METALS | POLYMERS | CERAMICS possible. At Eindhoven University of Technology, the Netherlands, Ph.D. candidate Camila Gomez reproduced the cooling process of Tata Steel’s blast furnaces in her lab and learned that us- ing warmer water can be better. During the rolling process, the steel slabs grow in length from 20 to more than 200 me- ters. To cool the steel, the slabs pass un- derneath water flowing at high speed. Gomez explains, “At the end, the steel passes through the jets of water at a speed of almost 80 km per hour; since the cooling process thus takes place at an extremely high speed, it’s difficult to study it at the factory.” To better adjust the industrial pro- cess to the production of new types of steel, it’s important to know exact- ly what happens to the cooling water near the steel’s surface. “Until now, there had been only experiments using stationary and slow-moving setups,” Gomez says. “We’ve now built a setup in Materials scientists use a pin-on-disk tribometer to impart shear deformation in materials. Courtesy of Arun Devaraj/PNNL. UNDERSTANDING SHEAR DEFORMATION Scientists at DOE’s Pacific North- west National Laboratory (PNNL) are using solid phase processing approach- es to create materials with improved properties. Recent work has focused on a lightweight aluminum silicon alloy widely used in the defense, aerospace, and automotive industries. The team used shear force to restructure the al- loy at the nanolevel. Distribution of the silicon was altered at the atomic level, making the microstructure much more robust than identical materials pro- duced conventionally. Using atom probe tomography and electron microscopy, the team ob- served how shear force changes the alloy’s microstructure. The silicon parti- cles fractured into smaller and smaller pieces until they were almost dissolved into the aluminum. The aluminum grains became much small- er. Both the aluminum and silicon phases displayed increased intermixing as a result of shear deformation. Understanding the influence of extreme shear deformation on a metal alloy’s micro- structure is crucial for optimizing novel solid phase materials pro- cessing methods. PNNL’s Solid Phase Processing Science Initiative funded this research as part of its efforts to advance the fundamental understanding of solid phase materials synthesis pathways and to enable the manufacture of next-generation materials and com- ponents that could make a difference in multiple industries, including aerospace, transportation, ener- gy, and metals recy- cling. pnnl.gov. WARM WATER TO COOL STEEL After flat-rolling steel slabs of vary- ing thicknesses, pro- ducers strive to cool the red-hot metal as quickly and evenly as By embedding titanium-based sheets in water, a team led by scientists from the RIKEN Center for Emergent Matter Science, Japan, created an adaptive material that can be converted from a hard gel to soft matter using temperature changes. Inspiration for the new inorganic material came from a sea cucumber, an aquatic creature that can change its skin from a hard layer to a kind of jelly to escape predators. www.riken.jp/en. BRIEF Camila Gomez tests the cooling process on hot steel in this customized lab setup.