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It is difficult to achieve high‐strength joints of metals to carbon‐fiber‐reinforced plastics (CFRPs) with high contents of continuous fibers with the poor fluidity. Herein, a special designed laser‐processing pretreatment is conducted on the surface of 5052Al, and friction‐lap joining (FLJ) is employed to join pretreated 5052Al to the CFRP with 50%–55% fiber content. The maximal tensile shear force and strength reach 4.06 kN and 18.04 MPa, respectively, with an increment of 72% compared to the untreated sample. It is the first time to achieve the high‐strength joint of Al alloys to CFRPs with high contents of continuous fibers via FLJ. The joining area and adhesion work are quantified by theoretical calculations, and the residual stresses are visualized by finite‐element analysis. The laser‐processing pretreatment changes the plain Al alloy surface structure into the rough and porous structure, largely increasing the mechanical interlocking effect of the joint, and also changes the Al alloy surface wetting behavior and increases the adhesion work from 59.66 to 81.17 mN m−1. That largely changes the chemical reaction feature between the CFRP and Al alloy, resulting in their tight bonding. In addition, the residual stresses weaken, which further improve the tight bonding effect. [ABSTRACT FROM AUTHOR]

Previous research has highlighted the importance of firm size for the propensity of technology licensing. However, the currently available knowledge regarding how firm innovation size affects the timing of technology licensing is limited, especially in developing economies such as that of China. Therefore, in the context of the Chinese patent system, this article builds a model for the timing decision of technology licensing from the perspective of licensors. This model theoretically reveals the relationship between firm innovation size and the likelihood of technology licensing at different time points. This article argues that there is a positive relationship between firm innovation size and the likelihood of technology licensing before the patent disclosure date; moreover, there is an inverted U-shaped relationship between the firm innovation size and the likelihood of licensing between the patent disclosure date and the grant date; however, firm innovation size is negatively correlated with the likelihood of licensing after the patent grant date. Empirical results based on 8737 first-time licensing data on invention patents of Chinese firms in 2001–2015 support all predictions. This study contributes to both the scholarly understanding of timing decision making in firms' technology licensing and the design of technology transfer policies for different firms in China. [ABSTRACT FROM AUTHOR]

Laser powder bed fusion (LPBF) is a typical additive manufacturing technology that offers significant advantages in the production of complex components. With the rapid heating and cooling characteristics of LPBF, a large amount of solid solution of alloying elements in the matrix can be achieved to form supersaturated solid solutions, thus enhancing the properties of LPBF alloys. For the unique microstructure, the heat treatment process needs to be adjusted accordingly. In this work, a Zr/Sc-modified Al-Mg alloy processed by laser powder bed fusion (LPBF) with relatively low cost and good mechanical properties was investigated. The fine microstructure was obtained under rapid solidification conditions. The nanoscale Al3(Sc,Zr) particles precipitated at the molten pool boundary during solidification. These particles, as effective heterogeneous nucleators, further refined the α-Al grains and improved the mechanical properties of the alloy. As a result, the alloy exhibited a heterogeneous microstructure consisting of columnar grains in the center of the molten pool and equiaxed grains at the boundaries. The rapid solidification resulted in the supersaturation of solute atoms in the α-Al matrix, which significantly enhanced the solid solution strengthening effect. With the LPBF processing parameters of a combination of a laser power of 250 W, a laser scanning speed of 833 mm/s, and stripe scanning mode, the tensile strength of the alloy reached 401.4 ± 5.7 MPa, which was significantly higher than that of the cast alloys with aging treatment (281.1 ± 1.3 MPa). The heat treatment promoted the formation of secondary Al3(Sc,Zr), Mn/Mg-rich phases. The ultimate tensile strength and elongation at fracture after aging at 325 °C for 2 h were 536.0 ± 1.7 MPa and 14.8 ± 0.8%, respectively. The results provide insight into the preparation of aluminum alloys with relatively low cost and excellent mechanical properties. [ABSTRACT FROM AUTHOR]