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The recrystallization and texture evolution of cold-rolled FeCrAl−0.65Nb and FeCrAl−1.2Nb alloys thin-wall tubes annealed at 600–900 °C for 1–600 min were investigated. The microstructures were characterized by electron back scattering diffraction, electron probe micro-analyzer and transmission electron microscopy. The Vickers hardness and room temperature tensile properties were tested. The results showed that the hardness of fully recrystallized FeCrAl−1.2Nb alloy was higher and more likely to recrystallize than FeCrAl−0.65Nb alloy. The weak texture strength of annealing sample was obtained and the proportion of //ND texture increased. The fine Laves phase distributed uniformly in FeCrAl−0.65Nb alloy had good pinning effect and inhibited recrystallization. Higher Nb content had little effects on tensile properties of thin-wall tube, and induced the formation of larger Laves phase. There was less fine Laves phase pinning in the large area adjacent to the blocky Laves phase, which resulted in easy recrystallization in FeCrAl−1.2Nb alloy.

Cr-coated Zr alloys are widely considered the most promising accident-tolerant fuel (ATF) cladding materials for engineering applications in the near term. In this work, Cr coatings were prepared on the surfaces of 1400 mm long N36 cladding tubes using an industrial multiple arc source system. Orthogonal analyses were conducted to demonstrate the significance level of various process parameters influencing the characteristics of coatings (surface roughness, defects, crystal orientation, grain structure, etc.). The results show that the arc current mainly affects the coating deposition rate and the droplet particles on the surface or inside the coatings; however, the crystal preferred orientation and grain structure are more significantly influenced by the gas pressure and negative bias voltage, respectively. Then, the underlying mechanisms are carefully discussed. At last, a set of systemic methods to control the quality and microstructures of Cr coatings are summarized.

Warm compression deformation of Fe–13.5%Cr–4.7%Al–2.0%Mo–0.70%Nb–0.40Ta (wt%) (FeCrAl) and Fe–13.5%Cr–4.7%Al–2.0%Mo–0.45%Nb–0.40Ta–0.11Zr (wt%) (FeCrAl–Zr) ferritic stainless steel was performed by a thermal simulation machine Gleeble 3800 at 600 °C and strain rates of 0.01–10 s−1. Before deformation, all the samples were solution-annealed for 2 h at 1150 °C for FeCrAl alloy and 1250 °C for FeCrAl–Zr alloy. The strain rate has little or no effect on peak stress, and the precipitates in matrix or grain boundary precipitates (GBPs) have no difference in the samples deformed at the strain rate 0.01 s−1 and 1 s−1 both in FeCrAl and FeCrAl–Zr alloys. The addition of Zr increased the proportion of low-angle grain boundaries (LAGBs). The Laves phase in FeCrAl alloy precipitated uniform in the matrix, while in FeCrAl–Zr alloy Laves phase precipitated at grain boundary and formed GBP. The LAGBs and Σ3 coincident site lattice (CSL) grain boundary both increased in FeCrAl–Zr alloy, which possessed some beneficial properties such as high-temperature creep resistance to the Fe–Cr–Al alloy. More interesting, twins were created by warm deformation, which was difficult in typical bcc ferrite alloy. These results could be expected to provide guidance for subsequent warm working processes for the alloy.

The CrMnFeCoNi-based composites with different multi-layer graphenes (MLGs) content (0 wt%, 0.2 wt%, 0.4 wt%, 0.6 wt%, 0.8 wt%) were prepared by powder metallurgy. The effects of the MLGs content on the mechanical and damping properties of the composites were studied specifically. The strength and hardness are obviously improved, and the tensile strength can reach 762 MPa. With the addition of MLGs, new damping mechanisms including the intrinsic damping of graphene and the interface damping are introduced, which lead the damping properties of composites to remain at a high level. As the content of MLGs increases, the Maximum internal friction (Q-1max) of the composites increases first and then decreases, and its maximum value is 0.0667.

The Fe65-xMn20Cr15Cox (x = 0, 5, 10, 15) high entropy alloys (HEAs) were prepared by mechanical alloying (MA) and spark plasma sintering (SPS). The effects of the configurational entropy on the microstructure, magnetic properties, and damping behaviors were investigated in this paper. As the Co content increased, the configurational entropy of the HEAs was increased from 0.88R to 1.23R, the magnetology performance was reduced significantly, but the peak of internal friction (IF) Q-1 increased monotonously. The maximum internal friction (IF) Q-1max achieved 0.073 when 15 at% Co element was added. With the configurational entropy increasing, in addition to the ferromagnetic damping mechanism, the dislocation damping mechanism was introduced in the HEAs. The synergistic effect of magneto-mechanical hysteresis and dislocation energy dissipation ensured the FeMnCrCo HEAs maintained high damping performance in a wide strain amplitude. Through the regulation of the microstructure, the possibility of application of the damping alloy under extreme conditions can be expanded.