Shaojie Gu 교수

Microstructural changes in conductive materials induced by electric current treatments, such as electromigration and electroplasticity, are critical in semiconductor and metal processing. However, owing to the inevitable thermal effect (Joule heating), the athermal effect on microstructural modifications remains obscure. This paper presents an approach of utilizing pre-micromachined structures, which obstruct current flow but maintain a thermal history similar to that of the matrix, effectively

Passive demodulation scheme using 3 × 3 coupler has been widely used in phase-sensitive optical time-domain reflectometry (φ-OTDR), interrogation of fiber Bragg gratings or fiber optic interferometric sensors, and sensor multiplexing. However, the asymmetry of the 3 × 3 coupler in real applications affects the demodulation performance seriously. We proposed an ameliorated 3 × 3 coupler-based demodulation algorithm using iteratively reweighted ellipse specific fitting (IRESF) to overcome the draw

• Up to 70 % microcrack healing-rate achieved by single high-energy HDPEC. • ECEM method proposed to correct FE model near crack tips. • No temperature or stress concentration occurs at microcrack tips. • Critical length (∼100 μm) identified to distinguish micro- and macrocracks. • Distinct repair strategies proposed for micro- and macrocracks. This study investigates the healing behavior of microcracks in a Ni-based superalloy using high-density pulsed electric current (HDPEC). Experimental res

Abstract This study comprehensively investigates the effects of high-frequency alternating current (AC) on the adhesion strength between metallic thin films and substrates as well as on the resistivity of metallic films. Under AC treatment at the optimal frequencies of 26, 37, and 38 MHz, the adhesion strengths of the Al, Cu, and Pt films to a substrate increase by 44.9%, 42.0%, and 101.8%, respectively, whereas their resistivities decrease by 22.6%, 38.4%, and 8.1%, respectively, at optimal fre

Abstract This study investigates the effects of high-frequency alternating current (AC) treatment on the microstructural evolution and electrical properties of electron-beam-deposited Cu thin films. After 60 min of AC treatment at a frequency of 500 kHz, the resistivity of the Cu thin films decreased to 97.9%, 95.6%, and 94.1% of their initial values at current densities of 30, 40, and 50 kA mm −2 , respectively. COMSOL simulations confirmed that the maximum temperature rise did not exceed 50 °C

Wheel-rail contact stress is foundation of the relationship between wheel and rail, and also an important basis for investigating further wear, surface damage and other problems of wheel and rail system. A three dimension elastic-plastic wheel/rail contact model is established using non-linear finite element method. The changes of wheel/rail normal contact stress, Mises stress and elastic-plastic deformations are analyzed under different conditions in heavy haul railway. A method is provided for

Efficient and rapid annealing treatments are critical for the sustainable forming and manufacturing of metallic materials, as well as for energy conservation and emission reduction in the manufacturing industry. We investigate the impact of high-density pulsed electric current (HDPEC) treatment on the recovery of work hardening in pre-strained SUS316 stainless steel and clarify the role of the athermal effect. The pre-strained samples exhibited significant work hardening, characterised by increa