Joining Technique Research Articles

Feasibility study of friction stir joining of aluminium with carbon fibre reinforced thermoplastic composite

During the last decades, environmental concerns and limited resources have set focus of research on lightweight, mechanically high-performing structures for the transportation industry, in order to reduce fuel consumptions and CO2 emissions. Friction Stir Joining (FSJ), as a variant of the Friction Stir Welding (FSW), is an innovative friction-based joining technique for metal-composite hybrid structures. Joining in the plasticized state below the melting temperature of the metal leads to a comparatively small heat-affected zone, so that only minor metallurgical changes occur. Additionally, only a short processing time and no additional weight in form of fasteners is needed. The main objective of this study is to evaluate the feasibility of metal-composite structures via FSJ, intending to enable a macro-mechanical interlocking bonding mechanism. Main focus was given to the integration of an aluminium nub inserted in a carbon fiber-reinforced polyphenylene sulfide (CF-PPS) sheet, to ensure sufficient plasticization of the aluminium part and no degradation in the polymer part. Residual stress arising from the friction stir joining process was also characterised using the Contour method. In this study, aluminium alloy 6082-T6 and CF-PPS composite sheets were used to produce long lap joints. Results have shown that the joints were created at almost constant peak temperature slightly above the melting temperature of the PPS but no physical-chemical changes were detected in the PPS. In addition, the influence of a PPS film as interlayer between the sheets was investigated in order to explore a method for preventing galvanic corrosion. Preliminary results indicate that it is not possible to integrate a metal nub to the CF-PPS without interrupting the PPS film. However, it is possible to create a nub within the PPS film.

Effect of variation in power input on dissimilar materials (Cu-Al) laser welding for battery manufacturing

Battery manufacturing inherently requires the joining of dissimilar materials. The performance of a joint is significantly derived from the joining technique as well as the process parameters, which, in turn, determine the life of the product. The current study discusses the efficacy of laser welding to develop dissimilar joints of thin sheets of Al and Cu for battery applications at varying power inputs. Thin sheets of aluminium and copper were welded using laser power inputs of 2.0 kW, 2.1 kW, and 2.2 kW. A power input of 2.1 kW results in 86 % higher weld penetration than the 2.0 kW. High power input results in through-thickness penetration, which drastically affects the mechanical strength of the joint. A weld joint developed at 2.1 kW shows a higher shear load of 800 N among all the power input parameters. An intermetallic layer forms at the weld interface for all three power inputs. However, the width of the intermetallic layer increases with the laser power input.

Weld interface metallurgy of dissimilar alloys welded by TIG technique

Abstract TIG welding is an important joining technique for fabricating quality structural components with industrial capability. Dissimilar alloy plates were combined using double-sided tungsten inert gas (TIG) welding. Microstructure evaluation of joints were anayzed by using scanning electron microscopy, optical microscope, energy dispersion spectrometry, elemental mapping, electron back scatter diffraction. DSAW technique increased joint penetration and reduced distortion of joints. In the weld metal zone, austenite, delta ferrite and lath martensite were dominant. The weld pool had high density of Cr7C3 and Fe3C phases and low density of CrFe7C0.45, FeNi, martensite, and Fe3Ni2 phases.

A route to fabricate low resistance joints between Eu–Ba–Cu–O bulk, single grain superconductors

The fabrication of large (RE)–Ba–Cu–O single grains [(RE)BCO], where RE = Y, Gd, Eu or Sm, with the complex geometries required for many practical applications is currently limited by the time intensive, complex nature of the grain growth process. In addition, the shapes achievable using established melt processing techniques, such as top seeded melt growth, are constrained significantly by the limited number of post-processing techniques readily available. Machining of these materials is also difficult given their ceramic-like mechanical properties, which makes them both brittle and hard. A potential alternative to the slow and inflexible melt growth processes is to join many small, single grains to form one large composite grain, connected by electrically and mechanically high-performance joints. A reliable joining technique would also greatly reduce the need for post-growth machining processes. In this work we extend our previous investigation of the use of single grain YBCO-Ag as an intermediate joining material to achieve effective and reliable superconducting joints between EuBCO-Ag bulk, single grain superconductors. The technique reported in the earlier studies requires limited specialist equipment and does not require tight process parameter control, since there is no need to re-grow the joining material at the intergrain interface. This technique is of particular interest given that the difference between the peritectic temperatures of the bulk superconductor and the intermediate joining material is large. We report the properties of seven joints engineered at different joining temperatures. The trapped field properties of the resulting joined samples were measured and the microstructure at the position of the joint examined. We demonstrate that this simple and the rapid joining technique makes it possible to manufacture composite grains in an industrially important (RE)BCO bulk superconductor with comparable superconducting properties to those of a single grain of similar dimensions.

Friction Stir Welding between Marine Grade Aa 5083 and HSLA Steel

The revolutionary method of solid-state joining technique has already attracted significant attention of advance welding and joining research community. The technique has been continuously developing for many alloy systems for similar and dissimilar joints. Recent research in these areas aiming to join complex dissimilar alloy pairs, composite, polymers, ceramics etc. This paper presents a study of friction stir welding between marine-grade aluminum alloy AA 5083 and HSLA steel, configured in a butt arrangement. The study investigates the evolution of Fe-Al series of intermetallic layer formation at the joint interface and its effective management to yield best joint efficiency. The FSW in the said alloy pairs yielded an 83.25% welding efficiency based on the aluminum alloy side strength. XRD analysis along with SEM examination revealed the formation of Al13Fe4 and Al5Fe2 as intermetallic compounds which was confirmed by the EBSD analysis. The obtained results are discussed in the paper considering the effect of the weld joint performance.

Energy Consumption and Tool Condition in Friction Stir Processing of Aluminum Alloys

AbstractFriction Stir Welding (FSW) and Friction Stir Processing (FSP) are solid-state joining and material processing techniques that have garnered considerable attention for their versatility and industrial applicability. In the present work, FSP was performed on AA 6056 T4, dealing with the issue of monitoring tool wear and assessing its impact on the process. The impact of tool wear on power requirements was analyzed, and it was expanded the understanding of tool behavior and its implications for the overall process performance. Specifically, variations in energy consumption, temperatures, and vibrations are observed with changing tool conditions. Further insights are provided by analyzing the microhardness and the pin volume ratio, which show distinct trends as the tool wears. Two tool maintenance ways are proposed, that are cleaning the tool with a sodium hydroxide solution and increasing the tool’s rotational speed. Both the strategies exhibit the potential to partially restore the tool’s initial characteristics. This study highlights the critical importance of assessing tool condition, energy consumption, and process sustainability, particularly in industrial settings where material processing requires efficiency and quality assurance.

ANALYSIS OF THE MICROSTRUCTURE AND MECHANICALPROPERTIES OF DUPLEX STEEL JOINTS

The article presents a study, the aim of which was to analyze the microstructure and mechanical propertiesof welded joints of austenitic-ferritic duplex steel X2CrMnNiN21-5-1. This steel is characterized by goodresistance to various types of corrosion, good strength properties and good weldability. Due to all theseadvantages, it is used in many industry sectors, and the main joining techniques are welding technologies. Inthis study, two joining techniques were used, SMAW (Shielded Metal Arc Welding) and GTA (Gas TungstenArc). The obtained welded joints were subjected to: macroscopic and microscopic metallographic tests,mechanical tests (static bending test and microhardness measurements), diffraction tests, and wear resistancetests. The results showed that the microhardness of the welds is similar and does not depend on the weldingmethod used. In the microstructure of the analyzed joints there are two phases: austenite (γ) and ferrite (δ),with different morphologies depending on the welding conditions, which affect the phase transformations.Material wear within the weld is greater than in the base material.

Progress in adhesive-bonded composite joints: A comprehensive review

Among the myriad joining techniques, the adhesive bonding technique is widely used to join complex large-scale composite structures because of its numerous advantages compared to traditional joining techniques. This article profusely analysed the various techniques for ameliorating the performance of composite joints, such as bonding methods (secondary bonding, co-bonding, co-curing, and multi-material bonding), surface modification techniques (plasma, laser surface treatment, surface grinding, etc.), additional reinforcement techniques (Z pin, wire mesh, nanofiller, etc), and different joint geometries (stepped joints, half-stepped joints, balanced joints, and scarf joints). Also, the effect of various adhesives and fabrication techniques on the static and dynamic performance of CFRP and GFRP-based joints was studied in detail. Moreover, this review addresses the finite element modelling and optimisation techniques on adhesively bonded joints. It has been observed that the bonding methods, surface modification to enhance the roughness of the adherend, addition of nanofillers, and variations in joint geometry greatly influence the shear strength, fracture toughness, fatigue, and vibration behaviour of FRP composite joints.

Influence of interfacial micro-textures on CFRTP-TC4 hybrid joint formation with laser assistant joining technique

To investigate the influence of interfacial micro-textures on the carbon fiber reinforced thermoplastic composites (CFRTP)-TC4 alloy hybrid joint formation process, a finite element model with micro-textures was established. The joint formation mechanism and the impact of joining parameters on heat input were analyzed. The results show that the existence of interfacial micro-textures will lead to an uneven distribution of the temperature field on the surface of polyamide and reduce the heat transferred to the surface of CFRTP. And, mechanical interlocks and new chemical bonds are generated in the joining process because of these micro-textures, which enhances the joining strengthen significantly. The optimized joining parameter window was also obtained and the joining strength was predicted by numerical simulation. With the numerical assistant, the CFRTP-TC4 joint with highest shear strength was obtained as the laser power and the welding speed is 130 W and of 2 mm/s, respectively.

Shear properties and failure mechanisms of adhesive bonded composite joint: Effect of glass particle reinforcement

AbstractHigh‐performance composite structures and effective joining processes are important for shipbuilding, and aerospace sectors to perform better in challenging situations. The importance of this study is to analyze the effect of glass powder‐modified adhesive and joining techniques such as co‐curing (CC), co‐bonding (CB), and secondary bonding (SB) on flexural, shear, and free vibrational characteristics such as natural frequency and damping factor for glass fiber‐reinforced polymer (GFRP) composites. Results revealed that, compared to SB and CB composite joints, 1 wt.% glass powder‐modified CC composite single lap joints (SLJ) enhanced the shear properties by 103.04% and 111.74%, respectively, due to rougher surface formation in the adhesive layer. As a result, it enhanced the fiber's adhesion to the matrix. On the other hand, CC bonded joints with 1 wt.% of glass powder exhibited the highest flexural strength (85.99 Mpa). The experimental free vibrational analysis showed that 1 wt.% glass powder CC composite had a high natural frequency, whereas higher wt.% glass powder increased the damping properties due to the matrix and fiber interaction. The current research reveals that CC technique with 1 wt.% of glass powder provided a significant improvement to the adhesively bonded composite's mechanical and free vibrational characteristics.Highlights Four distinct wt.% of glass powder were used to prepare the glass powder‐modified adhesive by sonication. SLJ glass fiber‐reinforced polymer composite joints were fabricated through CC, CB, and SB techniques Maximum shear and flexural strength were found at CC SLJ 1 wt.% glass powder. CC SLJ 1 wt.% glass powder enhanced better vibrational behavior. Failure surface analysis was conducted using FE‐SEM images.

Taxonomic position of holothurian Eupentactafraudatrix (Echinodermata, Holothuroidea).

Samples of the holothurian Eupentactafraudatrix (Djakonov & Baranova in Djakonov, Baranova & Saveljeva, 1958) from the Sea of Japan were studied and the relationships of the genera Eupentacta and Sclerodactyla, as well as related taxa, were evaluated on the basis of phylogenetic analysis of the mitochondrial DNA COI and 16S rRNA genes. Using three methods, phylogenetic trees were constructed, and the degree of reliability of topological reconstructions was estimated by means of a nonparametric bootstrap test for the neighbor joining (NJ) and maximum likelihood (ML) techniques, as well as by a posteriori probability for Bayesian inference (BI) analysis. Genetic data confirm the validity of the assignment of Cucumariafraudatrix to the genus Eupentacta Deichmann, 1938. The study of sequences obtained from the holothurian specimens collected in Russian waters, near the city of Vladivostok, and determined by morphological characters clearly indicate that these specimens belong to the genus Eupentacta and are assigned as E.fraudatrix . The specimens from China in GenBank named as Sclerodactylamultipes and used in the present study, were likely misidentified, and after re-examination they may be assigned to the genus Eupentacta, either as E.fraudatrix or another taxon. Analyses of morphological characters of S.multipes unequivocally affirm that this species must be excluded from Sclerodactyla Ayres, 1851 and is provisionally assigned to the genus Sclerothyone Thandar, 1989 based on the external morphological characters and the body wall ossicles.

Design of rose thorn biomimetic micro-protrusion for metals and CFRTP easily disassembled joining

This study focuses on the joining techniques for metals and carbon fiber reinforced thermoplastic (CFRTP) to address the pursuit of lightweight vehicles and high recycling efficiency. The innovative concept of ‘easy-disassembly joining’ is introduced for the first time, aiming for robust joint strength and efficient disassembly/recycling of end-of-life vehicles. Inspired by rose thorn morphology and natural performances, bionic micro-protrusions are explored as intermediate structures to facilitate the easy disassembly joining between metals and CFRTP. The primary focus of the study revolves around the design strategy of micro-protrusions inspired by rose thorns. The objective is to identify the most effective micro-protrusion shapes by understanding the interplay of its geometrical parameters, including base shape, apex position, profile curvature, and stress distribution under diverse loads. Utilizing static stress numerical simulations, the study conclusively identifies an elliptical base shape with the apex positioned slightly above the right edge of the structure. The outer profile adopts a circular arc, and the inner profile follows a conical curve. This configuration effectively mitigates stress concentration at the bottom, which interfaces with the metal substrate and the smaller areas around the apex. This research introduces an innovative concept for metal-CFRTP joining and applies bionic principles in engineering solutions. By promoting lightweight and sustainable structures through enhanced disassembly efficiency, it contributes to groundbreaking advancements in the field.

Comparative assessment of failure in single shear lap joints fabricated using various joining techniques

The current research endeavour reports the performance of single shear lap joints of flax/PP composite laminates. The joints were fabricated using mechanical joining, fusion bonding (ultrasonic and hot plate joining), and hybrid joining techniques (mechanical/ultrasonic joining and mechanical/hot plate joining). In case of the mechanical and hybrid joining, the effect of the bolt size, and number of bolts (single and double) on the tensile failure load was investigated. Pertaining to mechanical joining, the large bolt size and double bolts recorded higher tensile failure load compared to smaller bolt size and single bolt, respectively. Whereas with double bolts, no increase in the tensile failure load was observed for the hybrid joints, due to reduction in bonded area. The hybrid joints (mechanical/ultrasonic) recorded the maximum tensile failure load compared to all other type of joints. The load-extension behaviour and failure of joints was also examined. Expect mechanical joints, all other joints exhibited structural type of failure. In contrast, the mechanical joints resulted in a net-tension failure mode with failure line passing through the hole. However, the thermal decomposition and crystalline behaviour (XRD spectra) of developed joints did not vary significantly. The morphology of failed joints was examined using scanning electron microscope.

Contemporary Strategies for the Structural Design of Multi-Story Modular Timber Buildings: A Comprehensive Review

Modular timber construction embodies a pioneering and eco-friendly methodology within the building sector. With the notable progress made in manufacturing technologies and the advent of engineered wood products, timber has evolved into a promising substitute for conventional materials such as concrete, masonry, and steel. Beyond its structural attributes, timber brings environmental advantages, including its inherent capacity for carbon sequestration and a reduced carbon footprint compared to conventional materials. Timber’s lightweight nature, coupled with its versatility and efficiency in factory-based production, accelerates modular construction processes, providing a sustainable solution to the growing demands of the building industry. This work thoroughly explores contemporary modular construction using wood as the primary material. The investigation spans various aspects, from the fundamentals of modularity and the classification of modular timber solutions to considerations of layout design, structural systems, and stability at both the building and module levels. Moreover, inter-module joining techniques, MEP (mechanical, electrical, and plumbing) integration, and designs for disassembly are scrutinized. The investigation led to the conclusion that timber modular construction, drawing inspiration from the steel modular concept, consistently utilizes a structural approach based on linear members (timber frame, post-and-beam, etc.), incorporating stability configurations and diverse joint techniques. Despite the emphasis on modularization and prefabrication for adaptability, a significant portion of solutions still concentrate on the on-site linear assembly process of those linear members. Regarding modularity trends, the initial prevalence of 2D and 3D systems has given way to a recent surge in the utilization of post-and-beam structures, congruent with the ascending verticality of buildings. In contrast to avant-garde and bold trends, timber structures typically manifest as rectilinear, symmetric plans, characterized by regular and repetitive extrusions, demonstrating a proclivity for centrally located cores. This work aims to offer valuable insights into the current utilization of modular timber construction while identifying pivotal gaps for exploration. The delineation of these unexplored areas seeks to enable the advancement of modular timber projects and systems, fully leveraging the benefits provided by prefabrication and modularity.

Hybrid joints consisting of pre-tensioned bolts and a bonded connection—The influence of adhesives on the load-bearing capacity

This study explores the intricate mechanics of hybrid joints, which combine prestressed bolts and adhesive bonding, with a focus on increasing the joint capacity of steel structures. Despite their potential, the fundamental behaviour of these joints is not fully understood. The research focuses on unravelling the load-bearing capacity of these hybrid joints, emphasising the influence of the adhesive properties. The unique manufacturing process, involving the pre-tensioning of bolts while the adhesive is uncured, introduces additional dependencies not present in conventional adhesive joints. Analysis of the mechanical and physical properties of five adhesives provides key insights into the mechanics of load transfer and failure modes in hybrid joints, providing a comprehensive understanding. The study shows that load transfer occurs through micron-thin adhesive layers, highlighting the significant influence of adhesive properties on joint performance. Epoxies emerge as the top performers, with 2.5 times the average friction joint and more than five times the average bonded joint capacity, indicating their superiority in hybrid joint applications. Hybrid joints show significantly less variation than adhesive and friction joints, underlining their consistency and reliability in structural applications. When comparing hybrid and bonded joints with the same adhesive (SW7240), the variance was suppressed to one seventh by the application of preloaded bolts, with practical implications for design values based on quantiles. The study establishes correlations between joint strength and adhesive properties, emphasising the critical role of Young's modulus and tensile strength. It also finds that the elongation of hybrid joints at break is almost entirely dependent on load capacity, with viscosity having a lesser effect. Fracture surface investigations provide insight into the failure modes of hybrid joints, highlighting differences from those observed in frictional or purely bonded joints. This comprehensive study, combining experimental campaigns and in-depth analysis, provides valuable insights into the intricate relationships between joint capacity and adhesive properties in hybrid joints. The findings guide the selection of appropriate adhesives and provide the basis for the development of accurate load prediction methods, unlocking the full potential of hybrid joints and overcoming the limitations of conventional joining techniques in steel structures. Further research is encouraged to investigate the influence of adhesive class, post-tensioning stability and the nuanced mechanics of load transfer in these innovative joints.

Enhancing the Weld Quality of Polylactic Acid Biomedical Materials Using Rotary Friction Welding.

Polylactic acid (PLA) stands out as a biomaterial with immense potential, primarily owing to its innate biodegradability. Conventional methods for manufacturing PLA encompass injection molding or additive manufacturing (AM). Yet, the fabrication of sizable medical devices often necessitates fragmenting them into multiple components for printing, subsequently requiring reassembly to accommodate the constraints posed by the dimensions of the AM platform. Typically, laboratories resort to employing nuts and bolts for the assembly of printed components into expansive medical devices. Nonetheless, this conventional approach of jointing is susceptible to the inherent risk of bolts and nuts loosening or dislodging amid the reciprocating movements inherent to sizable medical apparatus. Hence, investigation into the joining techniques for integrating printed components into expansive medical devices has emerged as a critical focal point within the realm of research. The main objective is to enhance the joint strength of PLA polymer rods using rotary friction welding (RFW). The mean bending strength of welded components, fabricated under seven distinct rotational speeds, surpasses that of the underlying PLA substrate material. The average bending strength improvement rate of welding parts fabricated by RFW with three-stage transformation to 4000 rpm is about 41.94% compared with the average bending strength of PLA base material. The average surface hardness of the weld interface is about 1.25 to 3.80% higher than the average surface hardness of the PLA base material. The average surface hardness of the weld interface performed by RFW with variable rotational speed is higher than the average surface hardness of the weld interface performed at a fixed rotating friction speed. The temperature rise rate and maximum temperature recorded during RFW in the X-axis of the CNC turning machine at the outer edge of the welding part surpassed those observed in the internal temperature of the welding part. Remarkably, the proposed method in this study complies with the Sustainable Development Goals due to its high energy efficiency and low environmental pollution.

A State-of-the-Art Review on Direct Welding of Polymer to Metal for Structural Applications: Part 1 — Promising Processes

Structural lightweighting through the effective use of multiple materials has received increasing attention for fulfilling today’s demands for environmental sustainability in transportation systems. Direct dissimilar material joining methods (versus, e.g., traditional adhesive bonding or mechanical fastening) have become increasingly desirable since they offer process simplicity, production efficiency, and hermetic sealing, among others. In this two-part article, we provide a critical assessment of the state-of-the-art research and promising direct dissimilar material joining techniques reported over the last decades, with a particular emphasis on their potential for structural applications in Part I. As such, recent advances in advanced joint design and modeling methods for enabling optimum joint design for jointability and joint performance are presented along with some detailed examples for demonstrating their potential impacts on industrial applications in Part II. Finally, recommendations on future research and development directions are outlined for supporting the industry’s drive towards multi-material lightweighting.

Elucidating the in-process interfacial friction regime and thermal responses during inertia friction welding of dissimilar superalloys

Inertia friction welding (IFW) is a robust joining technique, particularly for hybrid structures composed of similar or dissimilar alloys. The highly transient thermal responses during friction heating produce variations in heat generation and temperature distribution, which are crucial for designing and controlling the IFW process. This study establishes a finite element (FE) model of the IFW process for dissimilar superalloys and investigates the transition of the interfacial friction regime and its impact on the transient thermal responses. The in-process state variables, including the frictional stress and heat flux, along with their spatial distributions at the welding interface, are obtained through FE simulations. The predicted results indicate that the transient transition of the friction regime produces two Coulomb friction zones accompanied by a shear friction zone. To capture the transient evolution of the friction regime, a novel phenomenological formula is developed. This model accurately predicts the shrinkage and disappearance of the two Coulomb friction zones and the enhancement of the shear friction zone from the initial 0.42 R0–0.87 R0 (where R0 is the workpiece radius) to the entire interface during the IFW process. The variations in interfacial heat flux, frictional stress, and temperature caused by the transition of the friction regime are comprehensively analyzed. Our results reveal that the transition from the Coulomb friction regime to shear friction regime at the interface is beneficial for temperature homogenization at the welding interface. The FE simulation results are validated against published experimental measurements, which confirms the accuracy and reliability of the FE model.

Metallurgical and mechanical properties evaluation of the activated flux tungsten inert gas weldments

The activated flux tungsten inert gas welding process is an attractive joining technique to increase the depth of penetration in a single pass. In the last two decades, the research on activated flux tungsten inert gas welding increased drastically. Despite enhanced weld penetration, activated flux tungsten inert gas is not frequently implemented in industries because of a lack of information about the process. However, research on activated flux tungsten inert gas welding has significantly increased in the last decade due to the widespread information related to the advancements in weld penetration and mechanical properties of the activated flux tungsten inert gas process. The activated flux tungsten inert gas welding process provides a high single pass depth of penetration along with good mechanical properties compared to the tungsten inert gas welding process. The current work offers an in-depth analysis of the activated flux tungsten inert gas welding process mechanism, advancement in activated flux tungsten inert gas methodology to improve weld bead geometry, and mechanical and corrosion behaviour of the weldments. The current work also highlights recent progress made in the field of dissimilar metal joining using the activated flux tungsten inert gas welding process.

Multi-layer solid-state ultrasonic additive manufacturing of aluminum/copper: local properties and texture

Ultrasonic additive manufacturing (UAM) is an advanced joining technique that utilizes ultrasonic vibrations to bond layers of metal foil together. UAM offers several benefits over traditional manufacturing methods, including enhanced design flexibility and reduced material waste, and its potential applications in various industries such as aerospace, automotive, and biomedical engineering are being actively explored. The study employs a nanoindentation apparatus to investigate the effect of the UAM process on the local mechanical properties of the bonded interface, along with changes in microstructure, which were investigated using scanning electron microscopy and electron back-scattered diffraction. The results revealed a significant correlation between material hardness and local plasticity. EBSD has revealed that the grain size distribution of Al far from the interface contains 57% of the grains less than 3 µm in size, while at the interface this number rises to approximately 78%, indicating that the average grain size decreases as it approaches the interface. This result is consistent with nanoindentation results that demonstrated a gradual change in the hardness of Al foil far from the interface to close to the interface (the maximum penetration depth near the interface was 500 nm less than far from the interface). Both EBSD and nanoindentation disclose the effect of work hardening close to the interface, which is related to dislocation accumulation with a density of 8.6×10-10cm-2\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$8.6\ imes {10}^{-10} {{\ ext{cm}}}^{-2}$$\\end{document} beneath the interface. The consistency of hardness and Young’s modulus with the pole figures and microscopic images demonstrated that plasticity flow and fine grain distribution would only occur in the vicinity of the interface in the softer metal region. Although the harder metal did not exhibit plasticity or recrystallization, the hardness, and Young’s modulus map indicated the formation of a layer of small grains close to the interface on the aluminum side owing to strain hardening and dynamic recrystallization.