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The fiber metal laminate is mainly used in the fuselage wall board, wing skin and other key parts of the aircraft. The structural parts mentioned above bear a large bending moment during the service, which requires that the fiber metal laminate should have the ability to resist bending deformation. In this study, fiber rare earth magnesium alloy super hybrid laminate, a new type of fuselage structure material was used as the research object. Three-point bending was used to test the bending strength of unidirectional and cross-ply rare earth magnesium alloy super hybrid laminates under different span-to-thickness ratios (L/h). SEM was used to observe the bending failure morphology of the laminate, and the progressive damage behavior of the laminate during the bending process was analyzed with finite element simulation. The research results show that the different L/h values have a certain effect on the bending strength of rare earth magnesium alloy super hybrid laminates. The effective bending failure L/h values of unidirectional and orthogonal rare earth magnesium alloy super hybrid laminates are 16-22 and 16-20 respectively. Through SEM observation and finite element analysis, it is concluded that the bending failure modes of laminate include elastic stage, plastic stage, fiber and epoxy resin matrix fracture stage, rare earth magnesium alloy fracture stage and laminate delamination stage.

Wheat (Triticum aestivum L.) is a crucial cereal crop, contributing around 20% of global caloric intake. However, challenges such as diminishing arable land, water shortages, and climate change threaten wheat production, making yield enhancement crucial for global food security. The heading date (HD) is a critical factor influencing wheat's growth cycle, harvest timing, climate adaptability, and yield. Understanding the genetic determinants of HD is essential for developing high-yield and stable wheat varieties. This study used a doubled haploid (DH) population from a cross between Jinmai 47 and Jinmai 84. QTL analysis of HD was performed under three phosphorus (P) treatments (low, medium, and normal) across six environments, using Wheat15K high-density SNP technology. The study identified 39 QTLs for HD, distributed across ten chromosomes, accounting for 2.39% to 29.52% of the phenotypic variance. Notably, five stable and major QTLs (Qhd.saw-3A.7, Qhd.saw-3A.8, Qhd.saw-3A.9, Qhd.saw-4A.4, and Qhd.saw-4D.3) were consistently detected across varying P conditions. The additive effects of these major QTLs showed that favorable alleles significantly delayed HD. There was a clear trend of increasing HD delay as the number of favorable alleles increased. Among them, Qhd.saw-3A.8, Qhd.saw-3A.9, and Qhd.saw-4D.3 were identified as novel QTLs with no prior reports of HD QTLs/genes in their respective intervals. Candidate gene analysis highlighted seven highly expressed genes related to Ca2+ transport, hormone signaling, glycosylation, and zinc finger proteins, likely involved in HD regulation. This research elucidates the genetic basis of wheat HD under P stress, providing critical insights for breeding high-yield, stable wheat varieties suited to low-P environments. [ABSTRACT FROM AUTHOR]

The basic formability of Glare 2A, Glare 2B and Glare 3 laminates was investigated by unidirectional tensile and three-point bending tests to explore the formability characteristics of Glare. Meanwhile, the failure characteristic of Glare was studied by scanning electron microscopy (SEM). The results indicate that the direction of the fiber has strong effects on the formability of Glare. The Glare 2A laminates exhibit the strongest resistance to plastic deformation. Meanwhile, it is also hard to deform in thickness direction.σ=σy+Kεn is used to fit the real stress-strain curves of three variants and proves the most suitable model, presenting the maximum correlation coefficient. Furthermore, Glare 2A laminates exhibit the most serious bending springback. Shrinkage and compression fracture are visible in the inner layer which bears compressive stress, and fiber fracture and delamination are found in the outer layer which bears tensile stress. On the contrary, Glare 2B laminates show the minimum springback, following with the observed fiber-matrix cracks. Finally, the accuracy of test results is verified by roll bending.

The Mg-3.0Nd-0.2Zn-0.4Zr (NZ30K) alloys were prepared by direct-chill casting (DCC) and sand mould casting (SMC) processes, respectively and their microstructures and mechanical properties were investigated. The results indicate that casting method plays a remarkable influence on the microstructure and mechanical properties of as-cast NZ30K alloy. The grain size increases from 35-40 μm in the billets made by the DCC to about 100-120 μm in the billets by the SMC. The aggregation of Mg12Nd usually found at the triple joints of grain boundaries in the billets prepared by SMC while is not observable from the billets by DCC. The tensile strengths and elongations of the billets are 195.2 MPa and 15.5% by DCC, and 162.5 MPa and 3.2% by SMC, respectively. The tensile strength of the alloy by DCC is remarkably enhanced by T6 heat treatment, which reached 308.5 MPa. Fracture surfaces of NZ30K alloy have been characterized as intergranular fracture by SMC and quasi-cleavage fracture by DCC, respectively.