Showing 235 results for Author: Ke An
Sep, 2026
Journal
Emerging high-precision technologies demand materials with exceptional dimensional stability and mechanical robustness, as even microscopic thermomechanical deformation can cause functional failure. However, a fundamental trilemma exists: High strength, ductility, and low thermal expansion are mutually exclusive, as strengthening-induced lattice distortions compromise the…
Sep, 2026
Journal
Endowing functional properties with mechanical responses in traditional metals has been a frontier topic, akin to transforming base metal into gold. Chromium and its alloys, with their functional deficiencies and limited ductility, serve as typical examples. Herein, we report a Cr96Fe4Ge1.3B1 alloy that unifies low thermal expansion (LTE, αl = 1.79 × 10-6 K-1, 200 − 315 K)…
Sep, 2026
Journal
In this work, 15-5 PH steel samples were fabricated using selective laser melting (SLM). The tensile properties were compared for the two different orthogonally-built systems for comparing anisotropy. The horizontally-built samples showed greater ultimate tensile strength, hardening behavior, and less yield strength as compared with the vertically-built sample. We applied…
Sep, 2026
Journal
Real-time in situ neutron diffraction was used to investigate the loading-direction dependence of phase-specific load sharing in a cold-rolled TRIP 780 sheet steel under tension at room temperature. A slightly lower yield stress and relatively faster initial strain hardening were observed for the tension along the rolling direction (RD), than those along the transverse dir…
Sep, 2026
Journal
Real-time in situ neutron diffraction was used to characterize the crystal structure evolution in a transformation-induced plasticity (TRIP) sheet steel during annealing up to 1000 °C and then cooling to 60 °C. Based on the results of full-pattern Rietveld refinement, critical temperature regions were determined in which the transformations of retained austenite to ferrite…
Sep, 2026
Conference Paper
Today’s automotive industry is witnessing increasing applications of advanced high strength steels (AHSS) combined with innovative manufacturing techniques to satisfy fuel economy requirements of stringent environmental regulations. The integration of AHSS in novel automotive structure design has introduced huge advantages in mass reduction while maintaining their structur…
Sep, 2026
Journal
After long-term thermal aging at 400 °C for 3000 h and 10,000 h, a cast duplex stainless steel exhibits promoted fatigue performance, including enhanced three-stage cyclic hardening and prolonged fatigue life. Utilizing in situ neutron diffraction, the phase-specific stresses are resolved, and their evolutions over entire fatigue cycling reveal the underlying mechanisms of…
Sep, 2026
Journal
High diffraction signal-to-background ratios (SBRs), the ratios of diffraction peak integrated intensity over its background intensity, are desired for a neutron diffractometer to acquire good statistics for diffraction pattern measurements and subsequent data analysis. For a given detector, while the diffraction peak signals primarily depend on the characteristics of neut…
Sep, 2026
Journal
Understanding the deformation mechanisms of materials at cryogenic temperatures is crucial for cryogenic engineering applications. In situ neutron diffraction is a powerful technique for probing such mechanisms under cryogenic conditions. In this study, we present the development of a compact cryogenic environment (CCE) designed to facil-itate in situ neutron diffraction e…
Aug, 2026
Journal
We have built and commissioned a compact in situ 3He polarizer based on spin-exchange optical pumping for the engineering materials diffractometer, named VULCAN, at the Spallation Neutron Source (SNS) at Oak Ridge National Laboratory. The system achieved 78% 3He polarization with a short pump-up time constant of 2.2 h. Its first deployment in an in situ half-polarized neut…
Aug, 2026
ORNL Report
The Robotic Interactive Control and Handling (RICH) system was further developed for supervised robotic sample handling at the VULCAN Engineering Materials Diffractometer. The previous platform demonstrated vision-guided sample detection, alignment, and manipulation, but its workflow support was centered on a predefined crucible-handling use case. The updated system retain…
Aug, 2026
ORNL Report
The automated data reduction on VULCAN is overhauled by using multithreading-capable python codes. Other than just creating reduced histogram data in GSAS format and reduce meta data as the prior mantid based routine, more automated services are included in the new reduction pipe line, including, generating GSAS-II format data, neutron and sample environment data slicing/c…