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- Real-time temperature monitoring during titanium alloy machining with cutting tools integrating novel thin-film sensorsPublication . Fernandes, Filipe; Martins, Bruno; Patacas, Carlos; Cavaleiro, Albano; Faia, PedroThis study explores the integration of titanium aluminum nitride (TiAlN) and zirconium aluminum nitride (ZrAlN) thin-film sensors into cutting tools for real-time temperature monitoring during machining of Ti6Al4V titanium alloy. These sensors, integrated into a multilayer coating for electrical and wear shielding, were deposited directly onto the tool surfaces and calibrated for temperatures up to 750 °C. Due to the integration into the multilayer coating, the sensors exhibit different β sensitivities across the temperature range, ranging from 108 to 825 K for TiAlN and from 950 to 6681 K for ZrAlN. The cutting tests conducted under various cutting conditions, such as cutting speed, feed rate, depth of cut, and cooling, revealed the influence of these parameters on the cutting temperature. Our findings indicate that the sensor position in the tool’s rake face is fundamental for measuring the cutting temperature. The study introduces an innovative tool connector for integration and signal retrieval of the cutting tool in a “plug-and-play” fashion, compatible with industry standards. Additionally, implementing wireless data transmission for real-time and in-situ temperature monitoring offers a pathway for integrating smart cutting tools into modern manufacturing environments, aligning with Industry 4.0.
- Multimetallic layered double hydroxides as efficient and durable oxygen evolution catalysts for anion exchange membrane water electrolysis at high current densitiesPublication . Yaowen Xu, Kaiyang Xu, Hao Tan, Haoliang Huang, Fei Lin, Chenyue Zhang, Jingwei Wang, Run Ran, Jinfeng Zeng, Zhipeng Yu, Sitaramanjaneya Mouli Thalluri, Lijian Meng, Dehua Xiong and Lifeng LiuThe development of efficient and durable electrocatalysts for the oxygen evolution reaction (OER) is critical for advancing anion exchange membrane water electrolysis (AEMWE) technology for sustainable hydrogen production. Herein, we report the synthesis of multimetallic NiCrFeMo layered double hydroxides (LDHs) via a facile microwave-assisted hydrothermal approach, engineered as high-performance OER catalysts for AEMWE operating at industrially relevant current densities. Advanced X-ray absorption spectroscopy (XAS) studies demonstrate that the interplay of Ni, Cr, Fe, and Mo tailors the electronic structure and coordination environment. Consequently, the NiCrFeMo LDHs exhibit remarkable OER performance, achieving overpotentials of 236 and 387 mV at 10 and 500 mA cm−2, respectively, in 1.0 M KOH, as well as outstanding durability at 500 mA cm−2 for 1000 hours with negligible degradation. In situ differential electrochemical mass spectroscopy (DEMS) and density functional theory (DFT) analyses reveal that the OER taking place on NiCrFeMo LDHs follows the adsorbate evolution mechanism, with minimal lattice oxygen involvement, contributing to the catalyst's longevity. When integrated into a prototype AEM electrolyzer cell as the anode catalyst, the cell demonstrates a current density of 1 A cm−2 at a relatively low voltage of 1.87 V and operates at 0.5 A cm−2 for 100 hours without decay, highlighting the potential of NiCrFeMo LDHs for practical applications. This work elucidates the synergistic effects of multimetallic compositions in LDHs, offering a strategy for designing cost-effective, high-efficiency OER catalysts to support green hydrogen production on scale.