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A Zr-based amorphous alloy (thickness = 2 mm) is welded by laser welding. The phase composition and microstructure of the welding joints under different laser powers are analyzed by optical microscopy, X-ray diffraction, and scanning electron microscopy. Mechanical properties of the welded joints under different laser powers are examined using microhardness and tensile testers. The glass forming ability and thermal stability of the welded joints are investigated using differential scanning calorimetry. With an increase in laser power, the degree of crystallization of welded joints increases, their microhardness is in the range 502.3-546.9 HV 0.2 , and tensile strength is up to 583 MPa (75% of that of the Zr-based amorphous alloy). Through the research of the article, it can be found that when the laser power increases, the crystallization degree of the welded joint first increases rapidly and then tends to be stable. The lower laser power should be used as far as possible in the case of penetration.

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A part consisting of Ni1Cu weathering steel is prepared by wire‐arc additive manufacturing (WAAM). Micro‐ and crystalline structures of this sample are analyzed spectro‐ and microscopically. Mechanical properties of the Ni1Cu steel (including microhardness, tensile strength, and impact resistance) are also assessed. Ni1Cu weathering steel possesses excellent forming quality and almost no defects when used for WAAM. The main features of the steel microstructure are blocks and needles, consisting of ferrite and granular bainite. The microhardness values in the transverse and longitudinal directions are uniform and equal to 169 and 177 HV0.2, respectively. Ni1Cu steel also demonstrates excellent mechanical properties with the transverse yield strength, tensile strength, elongation, and impact value of Charpy impact equal to 379 MPa, 517 MPa, 35.5%, and 147 J at −20 °C, respectively. The longitudinal direction values are equal to 376 MPa, 510 MPa, 31.5%, and 130 J at −20 °C, respectively. The Ni1Cu steel corrosion potential and current are equal to −719 mV and 5.8 × 10−3 mA cm−1, respectively.