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Abstract Joining processes especially for metallic materials play critical roles in manufacturing industries and structural applications, therefore they are essential to human life. As a more complex technique, under-liquid joining has far-reaching implications for national defense, offshore mining. Furthermore, up-to-now, the effective joining of metals in extreme environments, such as the flammable organo-solvent or the arctic liquid nitrogen, is still uninvestigated. Therefore, an efficient under-liquid joining approach is urgently called for. Here we report a method to join different types of metallic glasses under water, seawater, alcohol and liquid-nitrogen. The dynamic heterogeneity and liquid-like region expansion induces fluid-like behavior under ultrasonic vibration to promote oxide layer dispersion and metal bonding, allowing metallic glasses to be successfully joined in heat-free conditions, while still exhibiting excellent tensile strength (1522 MPa), bending strength (2930 MPa) and improved corrosion properties. Our results provide a promising strategy for manufacturing under offshore, polar, oil-gas and space environments.

Materials that exhibit very small dimensional changes with temperature, i.e., near-zero thermal expansion (NZTE) properties, find attractive prospects in fields such as precision instrumentation and aerospace. However, how to manually design and synthesize NZTE materials with high performance instead of laboriously exploring composition has been a long-standing challenge. In this study, based on the excellent bonding and forming abilities of metallic glass (MG), a composite with continuous regulation of thermal expansion was obtained by combining different volume ratios of MG with beta-LiAlSiO4 (beta-LAS) possessing negative thermal expansion (NTE). Interestingly, excellent NZTE performance of 0.693 and 1.587 ppm/K was achieved over the 150–700 K temperature range when the volume ratio of MG was 40% and 50%, respectively. In addition, the compressive strength of the NZTE composite reached 320 and 436 MPa for the above two ratios, respectively. The thermal shock resistance results show that the composite can withstand thermal cycling tests of not less than 80 times. The proposed strategy not only provides new NZTE materials with high performance but also facilitates a shift in the preparation of high-performance NZTE composites from laborious search to customizable design.

Developing a convenient and efficient way of tantalum (Ta) electrolytic capacitor manufacture process is of great importance in many fields, in which a time-saving and energy-efficient tonology of Ta powder consolidation is also desirable. As a typical way to consolidate Ta powder, powder sintering solves the consolidation difficulty of refractory metal like Ta, while the temperature that required are still high which means high energy costs. In the precent work, we tried to apply metallic glass (MG) as a glue to bond the Ta powder at a low temperature (513 k) and successfully obtained the MG-Ta composite due to the excellent thermoplasty of MG. The bonding mechanism between MG and Ta powder was then investigated and the results showed that the MG and Ta were well combined with each other. Moreover, the MG-Ta composite exhibits high performance enhancement with 57 % increased of specific capacitance and 32 % increased of mechanical property than pure Ta. In addition, the specific capacitance of the composite can be improved via acid etching and the mechanism was investigated. Our results provide a facile approach to consolidate the Ta powder with low cost as well as greatly enhance the performance for its application for solid Ta electrolytic capacitor.