Electron Backscatter Diffraction Research Articles

In-situ experimental investigation of the small fatigue crack behavior in CP-Ti: The influence of loading parameters and directions

This study quantitatively investigates the influence of loading parameters and directions on the behavior of small fatigue cracks (SFC) in commercially pure titanium (CP-Ti). It is observed that reductions in peak stress and increases in stress ratio correlate with a decrease in SFC growth rate and an intensification of growth rate fluctuations. Notably, crack growth along the transverse direction (TD) generally exhibits lower rates compared to that along the rolling direction (RD), with more pronounced fluctuations. Through metallographic analysis of crack paths, roughness-induced crack closure (RICC) is identified as a significant factor contributing to the observed variations in SFC growth behavior under different loading conditions. Furthermore, electron backscatter diffraction (EBSD) characterization reveals that crack propagation along the RD is primarily governed by prismatic slip, while TD samples exhibit more engagement of non-prismatic slip systems with higher activation stress. This results in a more tortuous crack path and pronounced crack arrest phenomena. Finally, a modified multi-scale rate prediction model based on the reference stress ratio method is proposed. Comparative analysis demonstrates that the modified model outperforms existing models by offering enhanced predictive capability across diverse loading conditions, thereby reinforcing its robustness in predicting SFC behavior of CP-Ti.

Microstructural and Mechanical Properties of WC-17Co Deposited Using Laser Direct Energy Deposition (LDED) and High-Velocity Oxygen Fuel (HVOF)

Abstract Recently, laser deposition technologies have made significant advancements in their ability to manufacture high-temperature metals and ceramics. One of these technologies, known as laser direct energy deposition (LDED), has the potential to deposit a wide range of materials from polymers to refractory materials, ceramics and functionally graded materials. This study evaluates major microstructural characteristics of WC-17 Co additively manufactured by LDED technology. A LDED-manufactured WC-Co sample was examined by optical microscopy (OM), scanning electron microscopy (SEM), energy-dispersive spectroscopy (EDS), and x-ray diffraction (XRD). Electron backscatter diffraction (EBSD) experiment was also performed to validate results obtained from XRD test. This material is commonly used for deposition of protective coatings due to its high hardness and excellent wear resistance. To this end, hardness and wear resistance of the LDED-processed samples were also investigated in this study. All the tests were also repeated on high-velocity oxygen fuel (HVOF)-deposited WC-Co with the same composition for the purpose of comparison. LDED sample showed slightly higher porosity (~4%) compared to the HVOF one (~3%). Both samples experience decomposition of the carbides into compound phases as indicated by XRD results. EBSD test results also confirmed the ones obtained from XRD and detected WC, Co, W2C, and W3Co3C in both samples while some more complex phases such as W9Co3C4 was found in LDED sample. The LDED-deposited sample also displays unique dendritic and eutectic structures that improve the hardness and wear properties compared to the homogenous HVOF coating instead of higher porosity level. The higher wear resistance of LDED sample is also associated with its higher hardness.

+SSLIP: Automated Radon‐Assisted and Rotation‐Corrected Identification of Complex HCP Slip System Activity Fields from DIC Data

ABSTRACTIdentification of crystallographic slip in metals and alloys is crucial to understand and improve their mechanical behaviour. Recently, a novel slip system identification framework, termed SSLIP (for slip system–based local identification of plasticity), was introduced to leap from conventional trace‐based identification to automated, point‐by‐point identification, exploiting the full deformation kinematics. Using sub‐micron‐scale digital image correlation (DIC) deformation fields aligned to electron backscatter diffraction (EBSD) data, SSLIP matches the measured in‐plane displacement gradient tensor to the kinematics of the optimal combination of multiple slip system activities, at each DIC datapoint. SSLIP was demonstrated to be successful on virtual and experimental case studies of FCC and BCC metals. However, for more challenging HCP crystal structures, the complete identification of all slip systems was found to be more challenging, posing limitations on automation and flexibility. To extend the capabilities of SSLIP, we propose an extended framework, hereinafter referred to as the +SSLIP method, which includes (i) a preselection of slip systems using a Radon transform, (ii) robustness to measured rigid body rotation by simultaneous identification of the local rotation field, (iii) identification of the two best matching slip systems for each data point and (iv) a procedure to determine groups of slip systems with in‐plane displacement gradient tensors that cannot be discriminated. This procedure yields the full (HCP) slip system activity maps for every slip system in each grain. The resulting objective identification method does not rely on the Schmid factor to select which slip system is active at each point. We show how slip systems from multiple slip families are successfully identified on virtual and real experiments on a Zn polycrystalline coating.

New-route of flux pinning enhancement in Nb3Al superconductor: density and orientation regulation of stacking faults by nano-oxide particles

Abstract The mechanism of critical current density (Jc) enhancement in rapid heating, quenching and transformation (RHQT) Nb3Al wires with nanoparticles was investigated from microscopic defects. As shown in transmission electron microscopy (TEM) results, stacking faults (SF) density in RHQT Nb3Al could be improved by incorporating nano-oxide particles, because the nanoparticles distorted the Nb3Al crystal lattice and the expansion of the distortion generated stacking faults. The macroscopic measurements based on electron backscatter diffraction (EBSD) showed that many stacking faults were parallel to the Lorentz force (FL//SF) in the pure sample, but orientation of stacking faults distributed randomly in the Nb3Al wires with nano oxide. Stacking faults that were normal to the Lorentz force (FL⊥SF) could hinder the motion of flux lines effectively and thus enhance the total flux pinning force (Fp). As a result, Jc of incorporated nano oxide Nb3Al wires were significantly elevated, where 1 at.% nano-ZrO2 and 1 at.% nano-Dy2O3 sample severally exhibited Jc values of 1.86×105 A/cm2 and 1.95×105 A/cm2@4.2 K,12 T, which improved by about 60% compared to the pure sample. The density and orientation regulation of stacking faults in RHQT Nb3Al revealed the new mechanism of Jc enhancement, which provided a new route to further improve the high-field Jc of Nb3A in future research.

Phase transformation at low temperature during low cycle fatigue and its Reversion in SS316L: An experimental and MD simulation study

The present study investigates the phase transformation processes in SS316L during Low Cycle Fatigue (LCF) and reversion heat treatment. The LCF tests were carried out at different strain amplitudes (0.6%, 0.8%, 1%, and 1.2%) at −80°C and 10−3 s−1 strain rate, which transforms γ-austenite phase to deformation induced martensite (DIM). Subsequently, all the deformed samples were annealed at 700°C for an hour to retransform DIM to the γ-austenite phase. Extensive microstructure analysis was performed using Electron Backscatter Diffraction (EBSD) and X-ray Diffraction (XRD) techniques to understand the phase transformation and reversion processes. Molecular dynamics simulated the DIM formation during LCF, revealing fcc to hcp (ε-martensite) and bcc (α’-martensite) phases in compression but no phase transformation during the tensile cycle.

Investigation of (mis-)orientation in zincblende GaN grown on micro-patterned Si(001) using electron backscatter diffraction

We present the application of electron backscatter diffraction (EBSD) as a technique for characterizing wurtzite (wz) and zincblende (zb) polytypes of GaN grown upon micropatterned Si (001) substrates. The Si substrate is etched to create parallel V-shaped grooves with opposing {111} facets before the deposition of GaN. EBSD revealed that wz-GaN growth fronts initially form on the {111} Si facets before undergoing a transition from a wurtzite to zincblende structure as the two growth fronts meet. Orientation analysis of the GaN structures revealed that the wz-GaN growth fronts had different growth orientations but shared the same crystallographic relationship with the zb-GaN such that ⊥{303¯8}wz∥⟨110⟩zb, ⟨112¯0⟩wz∥⟨110⟩zb, and ⊥{303¯4}wz∥⟨001⟩zb. Furthermore, the crystallographic relationship, {0001}wz-GaN∥{111}zb-GaN∥{111}Si, and alignment of the wz- and zb-GaN with respect to the Si substrate was investigated. The two wz-GaN ⟨0001⟩ growth directions were expected to coalesce at an angle of 109.5°; however, measurements revealed an angle of 108°. The resultant misalignment of 1.5° induces misorientation in the zb-GaN crystal lattice. While the degree of misorientation within the zb-GaN lattice is low, <1°, the zb-GaN lattice is deformed and bends toward the wz-GaN interfaces about the specimen direction parallel to the length of the V-groove. Further EBSD measurements over larger areas of the sample revealed that these results were consistent across the sample. However, it was also revealed that additional factors induce changes in the orientation of the zb-GaN lattice, which may relate to the initial growth conditions of the zb-GaN.

Ca3Ga2Ge3O12 Garnet Claddings for YAG Fiber Lasers

Abstract The feasibility of cladding single-crystal YAG fibers with melted Ca3Ga2Ge3O12 garnet (CGGG), with a melting point of 1370–1385 °C, was investigated. CGGG was melted and crystallized on single-crystal Y3Al5O12 (YAG) plates and fibers at controlled temperatures and heating/cooling rates. CGGG precursors were coextruded with single-crystal YAG fibers, melted, and crystallized using a travelling furnace, and using laser heated pedestal growth (LHPG). Single-crystal YAG fibers were also dip-coated with molten CGGG. The CGGG microstructures were characterized by optical microscopy, SEM, electron back-scatter diffraction, and TEM. In experiments with YAG plates, chemically induced grain boundary migration was observed at the CGGG-YAG interface. The CGGG viscosity was too low to apply thick claddings by dip coating in melt or by use of a traveling furnace, but this was not an issue for the LHPG based method. For cladding applied by LHPG,a ~ 1–2 μm thick layer intermediate in composition between CGGG and YAG was observed. All the CGGG claddings were polycrystalline, regardless of the method used; none were epitaxial with YAG. Cladding microstructures and the merit of the various cladding methods are discussed.

Microstructure characteristics and crystallographic orientation in dissimilar friction stir welding

This study examines the microstructural properties such as grain structure, grain boundary misorientation, and crystallographic texture of friction stir welding (FSW) joints under two cooling media (air and water cooling). The microstructural evolution of FSW joints was characterized using light and electron microscopy techniques. Specifically in electron microscopy, inverse pole figure maps, pole figures, and orientation distribution functions were evaluated for both conditions of FSW joints using Electron Back Scattered Diffraction (EBSD). The water-cooling FSW (WCFSW) joint exhibited the smallest grain sizes at the stir zone (SZ) location compared to the corresponding condition in the air-cooling FSW (ACFSW) joint. EBSD analysis revealed that grain size in the SZ was about 7.6 µm in the ACFSW joint and further refined to 3.2 µm in the WCFSW joint. The misorientation angle distribution of water cooling conditions generated high-angle grain boundaries. The main texture components observed in the FSW samples were Brass [{110} < 112>] and Goss [{110} < 001>]. Additionally, Orientation Distribution Function (ODF) analysis found a higher texture intensity in water-cooled joints than in air-cooled joints. The WCFSW joint also had higher ultimate tensile strength values and a faster strain hardening rate. This is because the grains were smaller, more dislocations were created, and suitable texture components and intensity were favorable.

Surface Integrity and Machining Mechanism of Al 7050 Induced by Multi-Physical Field Coupling in High-Speed Machining

Improving the surface quality and controlling the microstructure evolution of difficult-to-cut materials are always challenges in high-speed machining (HSM). In this paper, surface topography, defects and roughness are assessed to characterize the surface features of 7050 aluminum alloy (Al 7050) under HSM conditions characterized by high temperature, strain and strain rate. Based on multi-physical field coupling, the mechanism of microstructure evolution of Al 7050 is investigated in HSM. The results indicate that the surface morphology and roughness of Al7050 during HSM are optimal at fz = 0.025 mm/z, and the formation of surface defects (adherent chips, cavities, microcracks, material compression and tearing) in HSM is mainly affected by thermo-mechanical coupling. Significant differences are observed in the microstructure of different machined subsurfaces by electron backscatter diffraction (EBSD) technology, and high cutting speeds and high feed rates contributed to recrystallization. The crystallographic texture types on machined subsurface are mainly {110}<112> Brass texture, {001}<100> Cube texture, {123}<634> S texture and {124}<112> R texture, and the crystallographic texture type and intensity are significantly affected by multi-physical field coupling. The elastic–plastic deformation and microstructural evolution of Al7050 alloy during the HSM process are mainly influenced by the coupling effects of multiple physical fields (stress–strain field and thermo-mechanical coupling field). This study reveals the internal mechanism of multi-physical field coupling in HSM and provides valuable enlightenment for the control of microstructure evolution of difficult-to-cut materials in HSM.

Different post-heat treatment responses on microstructure and mechanical characteristics of maraging steel 1.2709 samples produced by LPBF

Abstract The study focuses on the enhancement of microstructural and microhardness characteristics of Laser-Based Powder Bed Fusion (LPBF) maraging steel 1.2709 with the effect of different heat treatment (HT) conditions including aging (AT), double aging (DAT), and solutioning (ST) and compared with the as-built (AB) condition. The samples were fabricated with the LPBF process parameters, utilizing 120 W of laser power, 500 mm s−1 of scanning speed, maintaining 20 μm layer thicknesses, with the laser spot width and hatch spacing of 0.0550 mm and 100 μm respectively in the argon environment with the 45° rotating raster scanning pattern. Further the as-built and heat treated samples were evaluated utilizing electron backscatter diffraction (EBSD), Field Emission Scanning Electron Microscope (FESEM), microhardness, x-ray diffraction (XRD) and relative density. The FESEM analysis indicated that the DAT samples exhibit a more refined and uniform interdendritic grain growth of precipitates Ni3 (Al, Ti) compared to the as-built sample, which exhibited porosity and lack of fusion. Aging reduces the presence of interlayer defects, while the solution-heat-treated sample reveals the formation of lath martensite. The microhardness exhibited an increase following three distinct heat treatment conditions: AB, AT, DAT, and ST, measuring 450 HV, 650 HV, 760 HV, and 520 HV, respectively. The ferrite content was recorded at 99.6%, 87.4%, 99%, and 99.4%, while the austenite content was 0.4%, 12.6%, 1%, and 0.6%. The grain size in the ferrite phase was 8.72 μm, 6.087 μm, 6.86 μm, and 0.32 μm, and in the austenite phase the grain size was 0.26 μm, 0.86 μm, 2.51 μm, and 6.89 μm.

Research on hot deformation characterization of a new weathering steel through processing map and microstructural observation

Investigations using hot compression tests on a new high-strength weathering steel revealed specific deformation behaviors across different conditions. These tests were performed at temperatures ranging from 850 to 1050 °C and at strain rates from 0.01 to 5 s−1. Results indicated that a decrease in the deformation temperature combined with an increase in strain rate notably enhanced both the maximum stress and strain achieved. Notably, above 900 °C and with strain rates below 0.1 s−1, the flow stress of the material reached a steady state at certain strain levels. At a strain rate of 1 s−1, irrespective of the temperature, the steel shows a continuous strain hardening behavior, achieving no stable flow stress state. Notably, when the true strain exceeds 0.8, an unusual increase in flow stress occurs, predominantly due to secondary work hardening effects. The microstructural changes in the deformed samples were examined using electron backscatter diffraction (EBSD), which helped elucidate the softening mechanisms inherent in this high-strength steel. Further, processing maps developed from true strains of 0.1–0.9, derived from the experimental flow stress data, suggest controlling the strain within 0.2–0.4 to minimize instability during hot working.

Study of the Intrinsic Factors Determining the Near-Threshold Fatigue Crack Propagation Behavior of a High-Strength Titanium Alloy

The resistance to near-threshold fatigue crack growth and its correlation with the microstructure of the Ti-5Al-3Mo-3V-2Zr-2Cr-1Nb-1Fe alloy were investigated. K-decreasing fatigue crack propagation rate tests were conducted on compact tension samples (ASTM standard) with a stress ratio R of 0.1 and a frequency of 15 HZ in a laboratory atmosphere. At a similar strength level of 1200 MPa, the sample with a fine basket-weave microstructure (F-BW) displayed the slowest near-threshold fatigue crack propagation rate compared with the samples with equiaxed (EM) and basket-weave (BW) microstructures. The fatigue threshold value (ΔKth) was 4.4 MPa·m1/2 for F-BW, 3.6 for BW, and 3.2 for EM. The fracture surfaces and crack profiles were observed by scanning electron microscopy (SEM) and electron backscatter diffraction (EBSD) to elucidate the mechanism of fatigue crack propagation in the near-threshold regime. The results revealed that the near-threshold crack growth in the three samples was primarily transgranular. The crack always propagated parallel to the crystal plane, with a high Schmid factor. In addition, the near-threshold fatigue crack growth behavior was synergistically affected by the crack tip plastic zone and crack bifurcation. The increased fatigue crack propagation resistance in F-BW was attributed to the better stress/strain compatibility and greater number of interface obstacles in the crack tip plastic zone.

A comprehensive study on the effect of high-temperature deformation level on microstructure development of austenitic stainless steel

ABSTRACT Austenitic stainless steel has been deformed to different strain levels at high temperatures and electron back-scattered diffraction has been done at the centre of the deformed samples to study the microstructure. A low strain of 0.22 develops deformation substructures and does not contribute much to the change in microstructure. An increase in strain value develops equiaxed grains and at 900 ℃, a necklace-type structure is observed. A decrease in average grain size with increased strain level is observed (except at 1200 ℃). A high fraction of high-angle grain boundaries with a significant fraction of Ʃ3 boundaries is observed at high temperatures and high-strain levels. The texture intensity showed the formation of strong [101] and [001] fibres. However, the intensity distribution between [101] and [001] varies with strain level and deformation temperature. Finally, discussions on the effect of high-temperature deformation on microstructure and texture development have been presented.

Titanium Oxide Formation in TiCoCrFeMn High-Entropy Alloys.

High-entropy materials, characterized by complex chemical compositions, are difficult to identify and describe structurally. These problems are encountered at the composition design stage when choosing an effective method for predicting the final phase structure of the alloy, which affects its functional properties. In this work, the effects of introducing oxide precipitates into the matrix of a high-entropy TiCoCrFeMn alloy to strengthen ceramic particles were studied. The particles were introduced by the ex situ method, such as TiO2 in the form of anatase, and by the in situ method, consisting of the reconstruction of CuO into TiO2. In both cases, it was assumed that after the homogenization process, carried out at 1000 °C, ceramic precipitates in the rutile phase, commonly considered a stable allotropic form of TiO2, would be obtained. However, the microscopic observations and XRD analyses, supported by EDS chemical composition microanalysis and EBSD backscattered electron diffraction, clearly revealed that, regardless of the method of introducing oxides, the final strengthening phase obtained was a mixture of TiO2 in the form of anatase with the Magnelli phase of Ti2O3. In this work, phase reconstruction in the Ti-O system was analyzed using changes in the Gibbs free energy of the identified oxide phases.

Exploring the role of volume energy density in altering microstructure and corrosion behavior of nitinol alloys produced by laser powder bed fusion

In the realm of materials science and engineering, the pursuit of advanced materials with tailored properties has been a driving goal behind technological progress. Scientific interest in laser powder bed fusion (L-PBF) fabricated NiTi alloy has in recent times seen an upsurge of activity. In this study, we investigate the impact of varying volume energy density (VED) during L-PBF on the microstructure and corrosion behaviour of NiTi alloys in both scan (XY) and built (XZ) planes. The microstructural evolution in both planes was characterized by electron backscatter diffraction and phase change temperatures were characterized using differential scanning calorimeter measurements. Electrochemical experiments were carried out to compare the specimens produced at high laser energy density and low laser energy density. The results indicate that employing high laser energy density in the production of NiTi alloy induces discontinuous dynamic recrystallization, contributing to grain refinement. This in turn enhances the corrosion resistance of the specimen. X-ray photoelectron spectroscopy was employed to examine the type of oxide layer that developed on the samples. The increased resistance to corrosion in a high laser energy density sample can be associated with the formation of a stable and homogeneous passive layer with enriched TiO2 as opposed to Ti2O3. This exploration has unravelled the intricate relationship between VED, the microstructure, and the corrosion properties of L-PBF fabricated NiTi alloys, offering valuable insights into their performance for diverse applications.

Crystal and Dislocation Characteristics of Ti-6Al-4V Alloy Under Effect of Laser Shock Peening.

Laser shock peening (LSP) is an effective method for enhancing the fatigue life and mechanical properties of Ti alloys. However, there is limited research on the effects of LSP on crystal structure and dislocation characteristics. In this study, Ti-6Al-4V alloy was subjected to laser shock peening with varying laser power levels. The influence of laser power on the microstructure of Ti-6Al-4V was investigated, with a focus on the evolution of the cross-sectional structure, crystallographic features, and dislocation behavior. These characteristics were analyzed using scanning electron microscopy (SEM), electron backscatter diffraction (EBSD), and transmission electron microscopy (TEM). Following laser shock peening, the surface grains of Ti-6Al-4V alloy exhibited a distinct preferred orientation and underwent significant refinement, resulting in the formation of nanocrystals. At a laser power of 8 J, the texture strength decreased to 5.19 mud. As laser power increased, a denser dislocation structure and high-density dislocation regions formed at the surface, and the subgrain size further decreased, reaching 66 nm at 8 J. These findings provide valuable insights into grain refinement and property enhancement, contributing to the understanding of process-microstructure-property relationships.

Microstructural evolution and hardening mechanisms in A286 superalloy thin-walled tubes subjected to cold forging

This paper aims to elucidate the microstructural evolution and hardening mechanisms in the thin-walled tube of A286 rivet sleeves subjected to cold forging. The strain distribution, microstructure, and hardness changes within the thin-walled tube were analyzed using Optical Metallography, Electron Backscatter Diffraction, a microhardness tester, and numerical simulations. The results indicate that cold forging leads to a 54% increase in the tube’s maximum hardness compared to the initial billet. Notable hardness gradients are observed along both the axial (329–356 HV) and radial (343–370 HV) directions. This hardness enhancement primarily originates from grain boundary strengthening and dislocation strengthening. The non-uniform strain distribution in the tube causes varying degrees of hardening effect, contributing to the observed hardness gradient. Additionally, Cold forging promotes the development of {111} fiber textures oriented parallel to the normal direction within the tube. These findings provide valuable insights for optimizing cold forging process parameters and enhancing the quality of aerospace blind rivets.

Effects of Pre-Deformation in Corrosion Fatigue Crack Growth of Al-Mg-Zn Alloy.

This study investigated the effect of pre-deformation on the corrosion fatigue crack propagation (CFCG) of Al-Mg-Zn alloy in a corrosive environment. Tensile tests at different pre-deformation levels and molecular dynamics simulations analyzed changes in dislocation density. Corrosion fatigue experiments were conducted in a 3.5% NaCl solution at room temperature, and crack propagation morphology was characterized using electron backscatter diffraction (EBSD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The results showed that tensile strength increased by 2.63% and 10.00% for 5% and 10% pre-deformation, respectively. The crack propagation threshold values were L2 (6.36 MPa·m1/2) > L0 (6.05 MPa·m1/2) > L1 (5.13 MPa·m1/2), attributed to increased dislocation density and material strength. At 5% pre-deformation, dislocation pile-ups created stress concentrations that facilitated crack propagation. In contrast, the non-uniform dislocation distribution at 10% pre-deformation enhanced both material strength and resistance to crack growth.

Effect of Tool Shoulder Profile on Grain and Texture Development in the Weld Interface Zone of Friction-Stir-Welded Dissimilar AA2024/AA7075 Joints.

Friction-stir-welded dissimilar AA2024/AA7075 joints have an apparent influence on grain and texture development at the weld interface due to differences in physical and chemical properties between the two aluminum alloys. In this work, the effect of tool shoulder profile on grain structure and texture evolution in the center interface zone (CIZ) and bottom interface zone (BIZ) of dissimilar AA2024/AA7075 joints were quantitatively studied by electron back-scattering diffraction (EBSD). The results indicate that abundant fine and coarse equiaxial grains are produced in the CIZ and BIZ of the joints produced with a concentric circle shoulder (CCS) and three-helix shoulder (THS), and the average grain size of the BIZ is lower than that of the CIZ for the same CCS or THS joint. A higher degree of recrystallization occurs in the CIZ of the joint with a CCS than that of the joint with a THS, while a similar degree of recrystallization is presented in the BIZ of the two joints. For the distribution of local misorientation angle between the two sides of the interface in the same CCS or THS joint, the CIZ manifests relatively uniform behavior, while the BIZ presents the characteristics of uneven distribution. Tool shoulder profile has a significant impact on the texture components at the weld interface, which results in different types of shear textures generated in the CIZ and BIZ of the two joints. It is beneficial to make out the microstructural evolution mechanism at the weld interface in dissimilar FSW joints for engineering applications in this study.

Effect of Zinc Element on Mechanical and Welding Properties of Cu–1.8Ni–0.45Si Alloy

Cu–Ni–Si alloy is widely used as the main material of lead frame. The process of alloying is an important method to improve the comprehensive performance of the alloy. Herein, Cu–1.8Ni–0.45Si (−0.5Zn) alloys are prepared. The variation trend and mechanism of Zn on the mechanical properties and welding properties are analyzed with scanning electron microscopy and electron backscattering diffraction. The results show that the addition of 0.5 wt% Zn can improve the brazing properties of the alloy while ensuring the tensile strength and conductivity of the material. Further quantitative analysis reveals that Zn addition enhances the contribution of precipitation strengthening to the alloy's mechanical properties, which is due to the reduction of the size of the particles of the precipitated phase by the addition of Zn. In addition, the addition of Zn can form a Zn‐enriched layer at the welding interface of the alloy, which has an obstructive effect on the diffusion and growth of the intermetallic compound (IMC) layer, effectively reducing the thickness of the IMC layer, inhibiting the formation of the Cu3Sn phase, and improving the mechanical properties of the alloy brazed joints.