Lunar surface temperature variations provide key information about the thermophysical properties of the regolith. To date, temperatures have been measured using telescopes and orbiter instruments, providing information from mid‐infrared to long infrared (IR) wavelengths. Here, we report on temperature measurements in the short‐wavelength IR at centimeter scales observed in situ by the Chang’E‐4 rover. These local observations are an important complement to the existing large‐scale data. We show that even at 2.39 µm, where reflected radiation dominates the spectrum, thermal information can be retrieved from the data. The observed thermal radiances and derived temperatures depend on the observation geometry, specifically the relative azimuth angle between Sun and detector. This indicates that surface roughness on subresolution (millimeter) scales causes a non‐Lambertian radiation pattern of the emitted flux that is per definition independent of the observation angle. This behavior must be considered when deriving temperatures and thermal properties of lunar regolith.

We know very well the Moon’s appearance in the visible wavelengths. What the Moon in the midinfrared (MIR) looks like is still a mystery. We present detailed appearance of the MIR Moon observed by a high‐resolution geostationary satellite and reveal the essence behind its appearance. The appearance of the MIR Moon is opposite to its normal visible appearance and shows limb darkening. Both the absolute and the relative brightness distribution of the MIR lunar disk changes with the solar incidence angle i. The signatures of the MIR Moon are controlled by both the reflection and the emission of the lunar surface. The center‐to‐limb temperature variation across the lunar disk is clearly shown. The slower decrease of the brightness temperature when moving away from the subsolar point than the Lambertian model represents topographic effects.

Aiming at the friction temperature is too high, excessive thermal stress problems of wet clutch engagement process, establish the three-dimensional model of wet multi disc clutch, using ANSYS workbench finite element software, the calculation process considering various displacement constraints, the boundary conditions are established. Convection field, stress field without oil groove and different types of the friction plate, and the temperature field and stress field of the friction plate are simulated. The research results provide a reference for the optimization design of wet multi disc clutch and the establishment of the clutch thermal management system.

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A microstructure variation in Al-1060 alloy after helium ion irradiation was revealed by a transmission electron microscope (TEM). The result shows that ion irradiation produced dislocations, dislocation loops, cavities and microcrystals in the irradiated layer. Dislocation-defect interactions were portrayed, especially the pinning effect of a dislocation loop and cavity on moving dislocation. Irradiation-induced stress was recognized as the main factor which impacted on the interaction of defect. Based on the dislocation inhibited with irradiation defects, the mechanism of microcrystal formation was proposed.