Multilevel gradient microstructures and twins enhancing wear resistance of laser additive manufactured CoCrFeNi high-entropy alloy introduced by synchronous ultrasonic impact treatment

Refinement effect of ultrasonic impact treatment on fatigue life of welded joints: A quantitative analysis based on crystal plasticity

Experimental and numerical study on residual stresses relief in 316 L austenitic stainless steel welded joints using layer-by-layer ultrasonic impact treatment

Plastic deformation behavior and strengthening mechanism induced by ultrasonic impact treatment in CoCrFeNiB0.15 high entropy alloy coatings

Effect of ultrasonic impact treatment on the wear and corrosion resistance of laser cladding Stellite 6 alloy coating

Effect of Ultrasonic Impact Treatment on the Residual Stress and Mechanical Properties of Naval Grade High-Strength Low-Alloy Steel Welded Joints

Structure and Properties of Plasma–Electrolytic-Oxidation Coatings Obtained on Д16Т Alloy under Different Electrical Parameters and Prior Ultrasonic Impact Treatment

Study on the microstructure, wear and corrosion resistance of CoCrFeNiMn high-entropy alloy coating via ultrasonic impact treatment

Influence of ultrasonic impact treatment on fatigue performance of novel double-sided full penetration U-rib welded joints

205A aluminum alloy was fabricated by wire-arc directed energy deposition (WA-DED) with and without ultrasonic impact treatment (UIT). The results indicated that UIT could lead to a large plastic deformation, improving surface forming quality and reducing internal porosity. Additionally, UIT facilitated the transformation of columnar grains into equiaxed grains, reducing the average grain size from 25 μm to 17 μm. After UIT, the mechanical properties improved, with ultimate tensile strength (UTS) and elongation (EL) reaching 255 MPa and 19% in the horizontal direction, and 245 MPa and 16% in the vertical direction, respectively. No significant anisotropy was observed.

Ultrasonic nondestructive evaluation of texture and elastic properties of Cu 37Zn brass subjected to shock compression and ultrasonic impact treatment

Study on the effects and mechanism of ultrasonic impact treatment on impact toughness of laser-welded joints of hot-rolled S355 steel

ABSTRACT A novel methodology combining WAAM with post-deposition ultrasonic impact treatment (UIT) was developed to address the challenges of excessive grain coarsening and compromised mechanical characteristics in ultrahigh-strength steel (UHSS) builds subjected to intensive thermal cycles. The research found that compared to the directly deposited samples, the grain refinement at the top of the ultrasonic impact-treated samples improved by 12.5%, while the refinement in the middle section increased by 15%. Quantitative analysis revealed differential strain localization patterns, with the surface-adjacent region demonstrating 40.63% KAM enhancement compared to 9.4% improvement in central bulk material. UIT-assisted WAAM processing significantly reduced anisotropy, where the horizontally oriented tensile strength reached 185.94 MPa, representing an 18.6% increment over conventional high-heat-input deposition techniques. This strengthening mechanism originates from the effects of UIT, which simultaneously induces grain refinement, elevates dislocation configuration complexity, and facilitates homogeneous Ni₃Ti intermetallic precipitation throughout the matrix. Therefore, by introducing ultrasonic impact treatment, the microstructural morphology of the deposited samples is improved, and their mechanical properties are enhanced, all while maintaining high deposition efficiency.

Predictive model of residual stress and microstructural evolution in 7075 aluminum alloy modified by ultrasonic impact and water jet combined surface treatment

In-situ microstructure evolution and recrystallization behavior of 321 stainless steel fabricated by wire and arc additive manufacturing and inter-layer ultrasonic impact treatment

Traditional narrow gap welding of thick titanium alloy plates easily produces dynamic molten pool flow instability, poor sidewall fusion, and excessive residual stress after welding, which leads to defects such as pores, cracks, and large welding deformations. In view of the above problems, this study takes 16-mm-thick TC4 titanium alloy as the research object, uses low-power pulsed laser-GTA flexible heat source welding technology, and uses the flexible regulation of space between the laser, arc, and wire to promote good fusion of the molten pool and side wall metal. By implementing instant ultrasonic impact treatment on the weld surface, the residual stress of the welded specimen is controlled within a certain range to reduce deformation after welding. The results show that the new welding process makes the joint stable, the side wall is well fused, and there are no defects such as pores and cracks. The weld zone is composed of a large number of α' martensites interlaced with each other to form a basketweave structure. The tensile fracture of the joint occurs at the base metal. The joint tensile strength is 870 MPa, and the elongation after fracture can reach 17.1%, which is 92.4% of that of the base metal. The impact toughness at the weld is 35 J/cm2, reaching 81.8% of that of the base metal. After applying ultrasound, the average residual stress decreased by 96% and the peak residual stress decreased by 94.8% within 10 mm from the weld toe. The average residual stress decreased by 95% and the peak residual stress decreased by 95.5% within 10 mm from the weld root. The residual stress on the surface of the whole welded test plate could be controlled within 200 MPa. Finally, a high-performance thick Ti-alloy plate welded joint with good forming and low residual stress was obtained.

Fatigue life extension of the prefatigued welded joints by ultrasonic impact treatment

Study on the Effect of Ultrasonic Impact Treatment on the Impact Toughness of S355J2 Steel Welded Joints

Study on the Cutting Performance and Mechanism of 7075-T6 Aluminum Alloy Enhanced by Ultrasonic Impact Treatment

Comparative study of heat treatment effects on the mechanical properties of laser directed energy deposited Ti6Al4V alloy with and without ultrasonic impact treatment