Laser-Induced Exothermic Bonding of SiCp/Al Composites with Nanostructured Al/Ni Energetic Interlayer

Abstract

In this study, SiCp/Al composites were bonded using the laser-induced exothermic bonding method. The nanostructured Al/Ni energetic materials were prepared by the high-energy ball-milling method and served as the bonding interlayer. The joint microstructure was characterized by SEM, EDS, TEM, and XRD. The effect of Zr content on the joint microstructure and shear strength was investigated. The results indicated that after the ball-milling process the Al and Ni particles underwent strong plastic deformations and were welded to each other, forming the nanostructured Al/Ni energetic materials with a lamellar structure. Compared with the raw powders, the location of the exothermic peak decreased by 42 K, and its exothermic performance was significantly improved. The exothermic reactions that occurred in the Al/Ni interlayer provided the required heat for the bonding process. Near the bonding interface, the interlayer could not react completely due to the cooling effect of the substrates, forming a mixture of residual metal particles and Ni-Al compounds. The addition of Zr content enhanced the interfacial reactions between the bonding interlayer and the SiCp/Al composites. The interlayer products transformed from NiAl to the eutectic organization of NiAl + Ni-Al-Zr, thus decreasing the pores in the joint and improving the bonding quality. With an increase in the Zr content, the joint shear strength first increased and then decreased. When the Zr content was 10 wt.%, the joint shear strength reached a maximum of 22 MPa.

Effect of High-Anisotropic Co2+ Substitution for Ni2+ on the Structural, Magnetic, and Magnetostrictive Properties of NiFe2O4: Implications for Sensor Applications

“…All three elements show two primary peaks with the designations 2p 3/2 and 2p 1/2 , as well as satellite (shake-up) peaks at higher binding energies. From the degeneracy (2 J + 1), it was discovered that the intensity ratio between 2p 3/2 and 2p 1/2 is almost 2:1. − For Ni (Figure a) and Co (Figure b), the intensity of the satellite peaks is comparatively high, whereas it is modest in the case of Fe (Figure c), showing that Ni and Co are in the 2+ oxidation state, while Fe is in the 3+ oxidation state. The Ni and Fe XPS peaks of NCFO change steadily toward higher binding energies as the Co-content ( x ) increases.…”

“…Tables , , and list the BE values of Ni 2+ , Fe 3+ , and Co 2+ , respectively. These binding energies are comparable to the values reported for the Ni 2+ , Fe 3+ , and Co 2+ ions in the literature. ,− …”