The present study conducts a comprehensive study on heat-treatment-induced cracking of Inconel 738 (IN738) alloy fabricated by laser powder bed fusion (LPBF) using scanning electron microscopy (SEM), energy dispersion spectrum (EDS), and electron backscatter diffraction (EBSD). The results indicate that the macroscopic crack is dominantly triggered by the strain-age cracking mechanism and propagates along grain boundaries. The initiation of cracking is facilitated by the superimposition of residual stress induced by the LPBF process and contraction stress induced by precipitation, while the reopening of compress pores at grain boundaries weakens the grain boundaries and provides fast channels for cracking. These results revealed the coupling effects in triggering heat-treatment-induced cracking, offering a fundamental guideline for crack control during heat treatment of additively manufactured IN738 alloy.

Magnesium and its rare-earth alloys are extensively studied for their lightweight properties and high specific strength, making them attractive for aerospace, automotive, and biomedical applications. However, their hexagonal close-packed structure leads to a strong basal texture, limiting plasticity and formability at room temperature. Considerable research has been devoted to texture control strategies, including alloying, thermomechanical processing, and recrystallization mechanisms, yet a comprehensive understanding of their effects remains an ongoing research focus. This review summarizes recent advances in texture regulation of rare-earth magnesium alloys, focusing on the role of RE elements (Gd, Y, Nd, Ce) and non-RE elements (Zn, Ca) in modifying basal texture and enhancing mechanical properties. The influence of key processing techniques, such as extrusion, rolling, equal channel angular pressing, and rotary shear extrusion, is discussed in relation to their effects on recrystallization behavior. Additionally, the mechanisms governing texture evolution, including continuous dynamic recrystallization, discontinuous dynamic recrystallization (DDRX), and particle-stimulated nucleation, are critically examined. By integrating recent findings, this review provides a systematic perspective on alloying strategies, processing conditions, and recrystallization pathways, offering valuable insights for the development of high-performance magnesium alloys with improved formability and mechanical properties.

Cu-0.4Cr (wt.%) alloys with the microalloying of Hf elements were subjected to a modified rolling–aging process to achieve high strength, high electrical conductivity and high ductility simultaneously. Transmission electron microscopy and X-ray line broadening analysis were conducted to characterize the microstructures of these alloys. Deformation twins and high-density dislocations were introduced into the copper alloys via the modified rolling–aging process and the microalloying of Hf, improving the mechanical properties of copper alloys. The Cu-Cr-Hf alloy with a reduced Hf content performed well in terms of strength, electrical conductivity and ductility. The microalloying of 0.4 wt.% Hf in the Cu-0.4Cr alloy was sufficient to achieve a good combination of high tensile strength (593 MPa), high uniform elongation (~5%) and high electrical conductivity (80.51% IACS).