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Article

Interfacial Diffusion and Copper Alloy Layer Wear Mechanism in Cu-20Pb-5Sn/45 Steel Bimetallic Composites

by
Yuanyuan Kang
1,*,
Guowei Zhang
2,
Yanling Hu
3 and
Yue Liu
1
1
Engineering Training Center, Taiyuan University, Taiyuan 030032, China
2
School of Material Science and Engineering, North University of China, Taiyuan 030051, China
3
China Shipbuilding Group Fenxi Heavy Industry Co., Ltd., Taiyuan 030027, China
*
Author to whom correspondence should be addressed.
Coatings 2025, 15(9), 1072; https://doi.org/10.3390/coatings15091072
Submission received: 1 August 2025 / Revised: 3 September 2025 / Accepted: 10 September 2025 / Published: 12 September 2025
(This article belongs to the Special Issue Surface Engineering Processes for Reducing Friction and Wear)
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Abstract

Cu-20Pb-5Sn/45 steel bimetallic composites were prepared using the solid–liquid composite method. The interfacial microstructure, bonding strength, and wear performance were systematically characterized to elucidate the mechanisms governing the solid-solution interface and copper alloy layer wear behavior. The results reveal that mutual diffusion of Cu and Fe forms a metallurgically bonded α-(Cu,Ni)/α-Fe interface with a diffusion layer thickness of approximately 10.7 µm and an interfacial shear strength of 227.58 MPa. Under dry sliding conditions, the average coefficient of friction was 0.145, with a wear rate of 7.3665 × 10−6 mm3/(N·m). The α-(Cu,Ni) matrix was reinforced by hard Cu3P and Ni-rich phases, which resist frictional shear stresses, while dispersed Pb particles provide self-lubricating properties, while the solid-solution interface hindered dislocation propagation, reducing dislocation pile-up and ensuring stable frictional performance.

Graphical Abstract

1. Introduction

Copper alloy/steel bimetallic composites are commonly utilized in low-to-medium load hydraulic pump cylinders, where the copper alloy layer forms a friction pair with the pump plunger for power transmission, while the steel layer provides high-strength mechanical support in coordination with the pump body [1,2,3,4]. During the startup phase, the copper alloy layer and plunger friction pair operate under dry or intermittent lubrication conditions, relying on the material’s inherent wear resistance [2,5]. The Cu-20Pb-5Sn alloy, known for its excellent self-lubricating properties, is typically used as the friction material metallurgically bonded with steel to form bimetallic composites [6]. In tribological studies of copper alloy/steel bimetals, Pervikov et al. employed electric explosion and magnetic pulse techniques to fabricate bimetallic materials, achieving reduced friction and wear through magnetic pulsing [7]. Zykova et al. used electron beam additive manufacturing combined with friction stir processing, reporting a 25% reduction in the friction coefficient post-processing [8]. Zhang et al. investigated the effect of varying Ag content in bimetals prepared via the solid–liquid composite method, finding that Ag addition enhanced interfacial shear strength by 58.3% and significantly improved wear resistance [9]. Similarly, Shi et al. optimized the comprehensive performance of copper alloy/steel bimetals using electromagnetic stirring, identifying optimal process parameters for superior tribological properties [10].
Existing literature often treats the interface and friction layer of bimetallic materials as separate entities. However, beyond the wear resistance and stable frictional performance of the copper alloy layer, the integrity of the bimetallic interface is critical to prevent delamination under shear stress [11,12]. Engineering practices have confirmed that weak interfacial bonding is a primary cause of bimetallic material failure [13,14]. Furthermore, Wang et al. compared single-metal lead bronze, brass, and bimetallic bronze/steel materials prepared via vacuum diffusion welding, finding that the presence of the steel layer reduced plastic deformation of the bronze during wear, resulting in superior tribological performance [15]. This indicates that the tribological properties of copper alloy/steel bimetallic composites are not solely determined by the copper alloy layer. During wear, frictional shear stress transfers through the copper alloy layer to the interface [16,17]. The interfacial microstructure, including the diffusion layer and grain boundaries, inevitably influences dislocation propagation and stress distribution during wear, thereby affecting surface deformation and overall stability of the copper alloy layer [18]. Additionally, wear-induced microstructural evolution in the friction layer, such as work hardening and dislocation pile-up, impacts the stress state at the interface [19,20]. These complex interactions are crucial for preventing material failure.
Despite numerous recent reports on the preparation, interface, and properties of copper alloy/steel bimetallic composites, research on the mechanisms linking interfacial microstructural features with the wear behavior of the copper alloy layer under sliding friction conditions remains limited [21,22,23]. Therefore, this study aims to fabricate Cu-20Pb-5Sn/45 steel bimetallic composites using the solid–liquid composite method. The microstructure, bonding strength, and tribological performance of the interface and copper alloy layer were systematically investigated, elucidating their interaction mechanisms under tribological loads. These findings offer a novel design strategy for layered bimetallic materials, particularly in applications requiring synergistic high strength and wear resistance.

2. Materials and Methods

2.1. Preparation of Bimetallic Specimens

The Cu-20Pb-5Sn/45 Steel bimetallic material was prepared by the solid–liquid composite method. 45 steel was used as the solid matrix material, and the original microstructure was mainly composed of polygonal ferrite and pearlite. The Cu-20Pb-5Sn was used as the liquid material. Table 1 shows the actual composition of the bimetallic determined by the Germany SPECTRO-MAXX (SPECTRO Analytical Instruments, Kleve, Germany) type direct reading spectrometer.
Figure 1a shows the process route of this experiment. The surface of the 45 steel substrate is contaminated with oil, rust, and oxide films, etc. Therefore, the surface of the substrate needs to be pre-treated before the solid–liquid composite process. Firstly, the steel substrate is ground with 240 # sandpaper to remove the rust and oxide films on the bonding surface. Then, it is immersed in NaOH (10%–15%) and HCL (10%–20%) solutions for 10 min each and subsequently cleaned with alcohol and dried. After the pre-treatment, a high-temperature active anti-oxidation coating (Na2B4O7:(CH2OH)2 = 20:13) is applied to the surface of the steel substrate to prevent oxidation of the steel substrate during the high-temperature preheating process. The preheating temperature of the steel substrate is 1150 ± 30 °C, and the preheating time is 30 ± 5 min. The pouring volume of each sample of copper alloy liquid is 500 g. The melting temperature is 1200 ± 30 °C. After the pure copper is melted, Ni, Zn, Pb, and Sn are added to the molten metal in sequence at intervals of 3–5 min according to their melting points from high to low. P is added to the copper liquid in the proportion of 1/3 for deoxidation and gas removal first. After adding all the other alloy elements, stirring is carried out with a graphite rod, and the remaining 2/3 is added to the alloy liquid. The bimetallic composite, prepared via the solid–liquid composite method, was sequentially cut from bottom to top into samples with thicknesses of 12.32 mm and 10 mm for microstructural analysis, friction performance testing, and shear strength evaluation. Figure 1b illustrates the sampling method for evaluating the microstructure and friction properties of the bimetallic material.

2.2. Microstructure and Performance Characterization

The copper alloy layer of the bimetallic composite was etched for 90–120 s using a 1:3 ammonia (NH3·H2O) and hydrogen peroxide (H2O2) solution, while the steel side was wiped with a 5% nitric acid alcohol solution for 5 s. OM (Zeiss AXIO Scope.A1, Carl Zeiss Microscopy GmbH, Oberkochen, Germany) was performed to observe the microstructure of the bimetallic interface and copper alloy layer. SEM (Hitachi SU5000, Hitachi High-Tech Corporation, Tokyo, Japan) was carried out using a 20 kV accelerating voltage and 50 nA probe current to study the microstructural features of the interface and copper alloy layer. EDS (X-Maxⁿ 50, Oxford Instruments, Oxford, United Kingdom) was employed to analyze atomic diffusion and phase distribution at the interface. EBSD (Symmetry S2, Oxford Instruments, Oxford, United Kingdom) was conducted using a 20 kV accelerating voltage, 10 nA probe current, and 0.5 μm step size to investigate crystal orientation, grain boundary angles, and grain size at the interface. TEM (FEI Titan Cubed Themis G2 300, Thermo Fisher Scientific, Hillsboro, OR, United States) was performed using a 300 kV accelerating voltage and 0.07 nm point resolution to characterize the crystal structure, solid-solution phases, and dislocation behavior at the interface.
Figure 2 illustrates the schematic for friction and wear testing and interfacial shear strength testing of the bimetallic samples. Friction tests were conducted using a ring-on-block configuration (MRH-3A friction testing machine, Jinan Hensgrand Instrument Co., Ltd., Jinan, China) under dry sliding conditions to evaluate the tribological performance of the copper alloy layer. As shown in Figure 2a, the copper alloy/steel bimetallic sample, a rectangular block, contacts a rotating ring-shaped counterbody. The copper alloy layer surface slides against the outer surface of the counterbody, with a normal load applied to the top of the sample perpendicular to the contact surface, generating friction force along the sliding. In the ring-on-block friction test, the maximum thickness of the copper alloy layer was maintained at 2 mm. The test conditions were as follows: ambient temperature, contact pressure of 0.66 MPa, sliding speed of 3.87 m/s, and test duration of 10 min. The counterbody was a GCr15 steel ring (HRC 60–62) with the following chemical composition (wt.%): C: 0.95%–1.05%, Si: 0.15%–0.35%, Mn: 0.25%–0.45%, Cr: 1.40%–1.65%, Fe: balance. The test aimed to simulate the dry friction conditions of a plunger pump cylinder during startup and early operation. The friction coefficient was recorded in real-time using a force sensor, and the wear rate was calculated using the formula W = V/(F·L), where V is the wear volume, F is the load, and L is the sliding distance. Each sample group was tested three times, and the average values were taken to minimize errors.
Shear strength testing at ambient temperature was conducted using a universal material testing machine (SUNS WAW-D, Shenzhen SUNS Technology Stock Co., Ltd., Shenzhen, China) to evaluate the bonding strength of the Cu-20Pb-5Sn/45 steel interface. The loading rate was maintained at ≤1 kN/s, and the interfacial shear strength was determined by averaging three test measurements. The shear strength was calculated using the formula τ = F/(π·d·h), where F is the maximum load, d is the interface diameter, and h is the thickness of the bimetallic sample, as illustrated in Figure 2b.

3. Results

3.1. Microstructure and Properties of Cu-20Pb-5Sn/45 Steel Bimetallic Interface

Figure 3 presents the microstructure of the Cu-20Pb-5Sn/45 Steel bimetallic composite fabricated via the solid–liquid composite method. A continuous, defect-free interface (free of inclusions, pores, or other defects) is formed between the copper alloy and steel layers. The microstructure on the steel side consists of a network of ferrite and lamellar pearlite. Additionally, a minor fraction of bainite is present, attributed to the rapid and non-uniform cooling conditions. The copper alloy layer is primarily composed of the copper-rich matrix, dendritic features, and free lead particles phases.
Figure 4 presents elemental line profiles of Cu and Fe concentrations across the Cu-20Pb-5Sn/45 Steel bimetallic interface, alongside the corresponding grain boundary distribution and grain size statistics. As evident in Figure 4a, mutual atomic diffusion occurs, forming a diffusion layer with an approximate thickness of 10.7 µm. Diffusion is predominantly characterized by Fe atoms migrating into the Cu side. The inverse pole figure (IPF) map in Figure 4b reveals that the diffusion layer forms a solid-solution interface, exhibiting an absence of pronounced crystallographic texture. Adjacent to the interface on the copper alloy side, the microstructure consists of columnar grains growing perpendicular to the interface. Furthermore, the average grain size in the copper alloy is significantly larger than that in the iron. Figure 4c displays the grain boundary misorientation angle distribution. Low-angle grain boundaries (LAGBs), represented by green lines, account for 62.2% of the total, while high-angle grain boundaries (HAGBs), indicated by black lines, constitute 37.8%. During shear deformation, LAGBs effectively dissipate dislocation propagation energy, whereas HAGBs impede dislocation transmission across the interface. This synergistic interaction contributes to enhanced interfacial strength [24]. During the solidification and cooling process, mutual diffusion of Fe and Cu atoms occurs at the interface. The increasing Fe concentration within the copper alloy layer near the interface refines its microstructure [18]. Which aligns with the finer grain structure observed in the copper alloy layer proximal to the interface in the IPF map.
Figure 5 presents the interfacial shear strength test results. The measured interfacial shear strength between the copper alloy and steel layers was 227.58 MPa. The shear force-time curve reveals that the interfacial shear force increased gradually during the initial steady-state phase. This robust initial performance is attributed to the solid-solution diffusion layer, its refined microstructure featuring columnar grains oriented perpendicular to the interface, and the synergistic effect of high-angle and low-angle grain boundaries, collectively contributing to the high interfacial bond strength.

3.2. Microstructure and Properties of Cu-20Pb-5Sn/45 Steel Bimetallic Copper Alloy Layer

Figure 6 shows the EDS mapping of element distributions in the copper alloy layer of the bimetallic composite. P and Ni exhibit dispersed dot and strip features, with closely aligned distributions. Pb is distributed as free particles within the matrix, Sn displays dendritic or segregated morphology, and Zn is uniformly distributed but at low concentration. Elemental compositions measured at different regions marked in Figure 6a are presented in Table 2. Location 1 corresponds to the Pb phase; at location 2, Sn has an atomic fraction of 15.19%, compared to 3.88% at location 4, indicating significant Sn segregation during solidification. At location 3, P combines with Cu to form the Cu3P phase, which also contains a high Ni content. At location 4, Ni and Cu form a continuous solid-solution phase, identified as α-(Cu, Ni).
In the molten state, the atomic radius of P (0.17 Å) is smaller than that of Cu (1.57 Å), facilitating preferential diffusion toward primary dendrite arms [25]. During solidification, the Cu3P phase precipitates at the liquid front, influenced by the non-equilibrium solidification of the solid–liquid composite method, leading to Ni segregation from the α-(Cu,Ni) phase and precipitation of a Ni-rich phase near Cu3P. Consequently, the distributions of P and Ni are closely aligned, as observed in Figure 6b,c.
To prevent interference from thermal effects or debris accumulation caused by extended wear testing, the tribological properties of the copper alloy layer in the Cu-20Pb-5Sn/45 steel bimetallic composite were assessed under dry sliding conditions over a 10 min duration. As depicted in Figure 7, the friction coefficient stabilizes at 0.14–0.15 after an initial run-in period of approximately 2 min, maintaining consistency for the remaining 8 min. This stability signifies the establishment of a uniform frictional interface following the run-in phase. The wear rate was 7.3665 × 10−6 mm3/(N·m), indicating that no significant material loss occurred within 10 min, consistent with the characteristics of stable contact under low-pressure post–run-in conditions.
Figure 8 presents the elemental mapping of the copper alloy layer surface after wear testing. Figure 8a shows the SEM morphology of the copper alloy layer, revealing parallel and continuous grooves on the worn surface, with no deep pits or cracks. A small amount of detached particles or wear debris is observed between the grooves, indicating uniform wear tracks without large-scale delamination or adhesive marks. Figure 8b illustrates the distribution of Pb, which appears as dispersed white spots, with some Pb particles embedded within the grooves or at surface protrusions. The absence of significant Pb detachment or aggregation suggests the formation of a Pb film during friction, contributing to self-lubrication. Figure 8c,d show relatively uniform distributions of Cu3P and Ni-rich phases, with minimal overlap with the grooves, indicating that these hard phases form a composite structure that resists wear. The elemental distributions reveal that Pb acts as a soft phase dispersed throughout the matrix, while P and Ni form hard phase agglomerates. No significant oxide or transfer layers are observed on the post-wear surface, indicating mild wear. The cutting and plowing actions of the counterbody on the copper alloy layer during sliding confirm abrasive wear as the dominant wear mechanism.

3.3. Interface Diffusion and Copper Alloy Layer Wear of the Mechanism Behavior

The microstructure and morphology of the interfacial diffusion layer were characterized using bright-field transmission electron microscopy (TEM), as shown in Figure 9. Figure 9b,c reveal variations in lattice constants across different orientations, indicating the formation of an α-(Cu,Ni) phase due to Ni solid solution in the Cu matrix. Point-scan analysis of the interfacial diffusion layer, presented in Figure 9d, confirms the presence of both α-(Cu,Ni) and α-Fe phases. During the solid–liquid composite process, Ni, with an atomic radius of 1.62 Å, closely matches that of Cu (1.57 Å), facilitating its solid solution in the Cu matrix and enhancing the lattice stability of the Cu-based phase [26]. Mutual diffusion of Fe and Cu atoms occurs at the interface, resulting in partial dissolution of Fe atoms into the copper alloy matrix, forming a metallurgically bonded α-(Cu,Ni)/α-Fe solid-solution interface.
Figure 10 illustrates the schematic architecture of the Cu-20Pb-5Sn/45 steel bimetallic system under frictional conditions. The combined effects of applied load and transient frictional heating induce several phenomena at the contact surface of the copper alloy layer, including plastic deformation, grain refinement, work hardening, oxidation reactions, and phase transformations [27,28]. These near-surface modifications impose significant transient shear stresses on the underlying interface, requiring robust interfacial bond strength to prevent catastrophic instantaneous fracture at the interface.
The presence of the α-(Cu,Ni)/α-Fe solid-solution interface creates a natural barrier to dislocation propagation. Under frictional loads, shear stresses are transmitted through the copper alloy layer to the interface, inducing dislocation motion and accumulation [29]. The incorporation of Ni increases lattice distortion in the α-(Cu,Ni) phase, impeding further dislocation transmission toward the 45 steel side. This dislocation-blocking effect reduces stress concentration at the interface, ensuring structural integrity under high shear stresses and significantly enhancing interfacial bonding strength. As friction progresses, the increasing dislocation density leads to accumulation and entanglement within the copper alloy matrix [30,31]. When these stresses propagate to the interface, the solid-solution layer effectively hinders further dislocation transmission, as evidenced by the observed dislocation pile-up at the α-(Cu,Ni)/α-Fe boundary, shown in Figure 11. This blocking mechanism minimizes the risk of interfacial delamination, ensuring stable frictional behavior.

4. Conclusions

The Cu-20Pb-5Sn/45 steel bimetallic composites, fabricated via the solid–liquid composite method, were systematically investigated for their interfacial and copper alloy layer microstructure and performance, yielding the following conclusions:
(1)
The Cu-20Pb-5Sn/45 steel interface forms a metallurgically bonded α-(Cu,Ni)/α-Fe diffusion layer with an interfacial shear strength of 227.58 MPa. This high bonding strength results from the synergistic contribution of fine columnar grains in the diffusion layer and the interplay of high- and low-angle grain boundaries.
(2)
Under dry sliding conditions, the copper alloy layer exhibits a stable friction coefficient of 0.145 and a low wear rate of 7.3665 × 10−6 mm3/(N·m). The excellent tribological performance is primarily attributed to the α-(Cu,Ni) matrix reinforced by hard Cu3P and Ni-rich phases, which resist frictional shear stresses, while dispersed Pb particles provide self-lubricating properties.
(3)
The α-(Cu,Ni)/α-Fe solid-solution interface effectively impedes dislocation propagation to the diffusion layer under frictional loads, reducing dislocation pile-up. This interfacial blocking effect, combined with the hard phases and self-lubricating Pb particles in the copper alloy layer, ensures stable frictional behavior during sliding.
Significant challenges remain in quantitatively correlating the microstructural evolution at the interface with friction-induced dynamic stresses in Cu-20Pb-5Sn/45 steel bimetallic composites. Real-time characterization of the dynamic microstructural changes in the copper alloy layer and interface under frictional loads is critical yet complex, limiting the broader application of these materials. Future research should integrate advanced in situ characterization techniques with multi-scale simulation methods to capture the real-time interactions between dislocations and the interface. Additionally, exploring lead-free alloying strategies and innovative interface design approaches could enable the simultaneous achievement of high strength and long-term tribological stability.

Author Contributions

Conceptualization, Y.K. and G.Z.; data curation, Y.L.; formal analysis, Y.K. and Y.H.; funding acquisition, Y.K.; investigation., Y.L. and Y.H.; project administration, Y.H.; validation, Y.K. and Y.H.; writing—original draft, Y.K., G.Z. and Y.L.; writing—review and editing, Y.K., G.Z., Y.L. and Y.H. All authors have read and agreed to the published version of the manuscript.

Funding

This research was funded by the Shanxi Provincial Basic Research Program Young Scientists Fund (Grant No. 202303021222228) and the Scientific and Technological Innovation Programs of Higher Education Institutions in Shanxi (Grant No. 2023L381).

Institutional Review Board Statement

Not applicable.

Informed Consent Statement

Not applicable.

Data Availability Statement

All data generated or analyzed during this study are included in this published article.

Conflicts of Interest

Author Yanling Hu was employed by the company China Shipbuilding Group Fenxi Heavy Industry Co., Ltd. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

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Coatings 15 01072 g001
Figure 1. Schematic diagram for fabrication of Cu-20Pb-5Sn/45 Steel bimetallic composite materials: (a) Process route of the experiment; (b) Sampling methods. 1. Crucible; 2. Cu-20Pb-5Sn alloy liquid; 3. 45 Steel; 4. Active agent coating; 5. Shear strength test sample; 6. Microstructure and friction test sample.
Figure 1. Schematic diagram for fabrication of Cu-20Pb-5Sn/45 Steel bimetallic composite materials: (a) Process route of the experiment; (b) Sampling methods. 1. Crucible; 2. Cu-20Pb-5Sn alloy liquid; 3. 45 Steel; 4. Active agent coating; 5. Shear strength test sample; 6. Microstructure and friction test sample.
Coatings 15 01072 g001
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Figure 2. Schematic of friction and interfacial shear strength testing for bimetallic samples: (a) Schematic of the friction test; (b) Schematic of the shear test.
Figure 2. Schematic of friction and interfacial shear strength testing for bimetallic samples: (a) Schematic of the friction test; (b) Schematic of the shear test.
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Figure 3. Cu-20Pb-5Sn/45 Steel interface and copper alloy layer microstructure: (a) Metallography at Cu-20Pb-5Sn/45 Steel interface; (b) Metallography at Cu-20Pb-5Sn alloy layer.
Figure 3. Cu-20Pb-5Sn/45 Steel interface and copper alloy layer microstructure: (a) Metallography at Cu-20Pb-5Sn/45 Steel interface; (b) Metallography at Cu-20Pb-5Sn alloy layer.
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Figure 4. Microscopic characterization of the Cu-20Pb-5Sn/45 Steel interface: (a) Interface diffusion line scanning; (b) Grain size distribution; (c) Grain boundary orientation difference distribution.
Figure 4. Microscopic characterization of the Cu-20Pb-5Sn/45 Steel interface: (a) Interface diffusion line scanning; (b) Grain size distribution; (c) Grain boundary orientation difference distribution.
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Figure 5. Cu-20Pb-5Sn/45 Steel interfacial shear strength.
Figure 5. Cu-20Pb-5Sn/45 Steel interfacial shear strength.
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Figure 6. EDS element mapping of different element distributions in bimetallic copper alloy layer: (a) SEM morphology; (b) P surface distribution; (c) Ni surface distribution; (d) Zn surface distribution; (e) Pb surface distribution; (f) Sn surface distribution.
Figure 6. EDS element mapping of different element distributions in bimetallic copper alloy layer: (a) SEM morphology; (b) P surface distribution; (c) Ni surface distribution; (d) Zn surface distribution; (e) Pb surface distribution; (f) Sn surface distribution.
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Figure 7. Copper alloy layer friction coefficient curve.
Figure 7. Copper alloy layer friction coefficient curve.
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Figure 8. Scanning of the elemental surface of the copper alloy layer after friction: (a) SEM morphology; (b) Pb surface distribution; (c) P surface distribution; (d) Ni surface distribution.
Figure 8. Scanning of the elemental surface of the copper alloy layer after friction: (a) SEM morphology; (b) Pb surface distribution; (c) P surface distribution; (d) Ni surface distribution.
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Figure 9. TEM bright field image and calibration of solid solution interface: (a) TEM bright field image; (b) High-resolution imaging of the copper alloy side at the interface; (c) Selected area electron diffraction; (d) Point-scan analysis of the diffusion layer.
Figure 9. TEM bright field image and calibration of solid solution interface: (a) TEM bright field image; (b) High-resolution imaging of the copper alloy side at the interface; (c) Selected area electron diffraction; (d) Point-scan analysis of the diffusion layer.
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Figure 10. Frictional microstructural evolution of Cu-20Pb-5Sn/45 Steel bimaterial system: (a) Structure before wear; (b) Structure after wear.
Figure 10. Frictional microstructural evolution of Cu-20Pb-5Sn/45 Steel bimaterial system: (a) Structure before wear; (b) Structure after wear.
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Figure 11. TEM observation of dislocation propagation hindered by solid-solution interface: (a) α-(Cu,Ni)/α-Fe interface exhibiting dislocation distribution; (b) High-resolution view of dislocation propagation within the structure.
Figure 11. TEM observation of dislocation propagation hindered by solid-solution interface: (a) α-(Cu,Ni)/α-Fe interface exhibiting dislocation distribution; (b) High-resolution view of dislocation propagation within the structure.
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Table 1. Main chemical composition of bimetallic materials (wt.%).
Table 1. Main chemical composition of bimetallic materials (wt.%).
ComponentCSiMnPbSnZnPNiCuFe
Cu-20Pb-5Sn00019.854.731.750.082.38Bal.0
45 Steel0.450.210.68000000Bal.
Table 2. Elemental content at different positions in Figure 6a.
Table 2. Elemental content at different positions in Figure 6a.
Locationat.%
CuZnSnPNiPb
112.81.341.425.043.4575.95
277.311.0615.194.391.820.23
365.120.260.3624.779.460.03
483.21.93.880.3110.660.05
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MDPI and ACS Style

Kang, Y.; Zhang, G.; Hu, Y.; Liu, Y. Interfacial Diffusion and Copper Alloy Layer Wear Mechanism in Cu-20Pb-5Sn/45 Steel Bimetallic Composites. Coatings 2025, 15, 1072. https://doi.org/10.3390/coatings15091072

AMA Style

Kang Y, Zhang G, Hu Y, Liu Y. Interfacial Diffusion and Copper Alloy Layer Wear Mechanism in Cu-20Pb-5Sn/45 Steel Bimetallic Composites. Coatings. 2025; 15(9):1072. https://doi.org/10.3390/coatings15091072

Chicago/Turabian Style

Kang, Yuanyuan, Guowei Zhang, Yanling Hu, and Yue Liu. 2025. "Interfacial Diffusion and Copper Alloy Layer Wear Mechanism in Cu-20Pb-5Sn/45 Steel Bimetallic Composites" Coatings 15, no. 9: 1072. https://doi.org/10.3390/coatings15091072

APA Style

Kang, Y., Zhang, G., Hu, Y., & Liu, Y. (2025). Interfacial Diffusion and Copper Alloy Layer Wear Mechanism in Cu-20Pb-5Sn/45 Steel Bimetallic Composites. Coatings, 15(9), 1072. https://doi.org/10.3390/coatings15091072

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