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A Zr 55 Cu 30 Ni 5 Al 10 plate-like bulk metallic glass (BMG) was prepared using copper mold suction casting. Additionally, alloy powders with the same nominal composition were synthesized. The alloy powders were welded or melted to the cleaned surface of the BMG with a laser beam acceleration voltage of 60 kV, a beam current range from 60 to 100 mA, a welding speed of 60 mm/s, as well as an impulse width of 3.0 ms. The effect of consubstantial composition welding on the microstructures and properties was investigated. The molten and subsequently solidified metallic mixtures remain an amorphous structure, but the enthalpy of the welded or melted position varies due to the combination of the micro-structural relaxation and nano-crystals precipitated during the energy inputs. The surface layers of the BMG can be significantly intensified after welding processes; however, the heat-affected zones (HAZs) exhibit a slight degradation in mechanical properties with respect to the BMG matrix. This study has important reference value for specialists working on the promotion of applications of BMGs.

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In order to study the wear performance of Ti/Al coating under different loads, split-target magnetron sputtering device was used to prepare a Ti/Al composite coating on the surface of 304 stainless steel, the friction and wear test of the coating with 3.5%NaCl treatment was carried out. Scanning electron microscope (SEM), scratching instrument, EDS, three-dimensional surface topography instrument and other equipment were used to investigate the physical and chemical properties of the coating. During magnetron sputtering coating, Ti and Al atoms are stacked to form a Ti-Al binary phase, and TiAl3 intermetallic compounds are enriched in the coating. The wear experiment shows that the wear rate of the Ti/Al coating is significantly lower than that of the substrate, moreover, the wear rate increases uniformly with the load. The friction coefficient of the Ti/Al coating is lower than the friction coefficient of substrate in the table wear stage under different loads. The friction coefficient of the coating decreases as the load increases. At low loads, the coating main form of wear is the surface abrasive wear with furrows. With increasing the load, the coating wear form is mainly represented that the reduction of abrasive wear and the generation of micro-cracks on the surface, which in turn produces scaly flaking.