Journal of Thermal Spray Technology最新文献

{"title":"Innovative Coatings for a Greener Sky: The 2026 Strategic Roadmap for Thermal Spray and PVD Coatings","authors":"Andrew Ang,&nbsp;Thibaut Archer,&nbsp;Farzam Arhami,&nbsp;Mettupalayam Balachander,&nbsp;Kantesh Balani,&nbsp;Dominique Billières,&nbsp;Ann Bolcavage,&nbsp;Giovanni Bolelli,&nbsp;Marjorie Cavarroc-Weimer,&nbsp;Sophie Costil,&nbsp;Nicholas Curry,&nbsp;Alain Denoirjean,&nbsp;Ali Dolatabadi,&nbsp;Alice Dolmaire,&nbsp;William Duarte,&nbsp;David Dublanche,&nbsp;Julien Escobar,&nbsp;Alice Fabre,&nbsp;Gaël Fick,&nbsp;Guillaume Fradet,&nbsp;Frank Gärtner,&nbsp;Edward J. Gildersleeve,&nbsp;Mohit Gupta,&nbsp;Jonathan Gutleber,&nbsp;Makoto Hasegawa,&nbsp;Bryan J. Harder,&nbsp;Brian Hazel,&nbsp;Hendrik Heinemann,&nbsp;Xianghui Hou,&nbsp;Tanvir Hussain,&nbsp;Eric Irissou,&nbsp;Mehdi Jadidi,&nbsp;Cédric Jaoul,&nbsp;Maria Ophelia Jarligo,&nbsp;Bertrand Jodoin,&nbsp;Shrikant Joshi,&nbsp;Andreas Killinger,&nbsp;Jolanta E. Klemberg-Sapieha,&nbsp;Komal Laul,&nbsp;Chang-Jiu Li,&nbsp;André C. Liberati,&nbsp;Rocco Lupoi,&nbsp;Gilles Mariaux,&nbsp;Ludvik Martinu,&nbsp;André McDonald,&nbsp;Christian Moreau,&nbsp;Majid Nabavi,&nbsp;Aleksandra Nastic,&nbsp;Ahmet Hilmi Paksoy,&nbsp;Cédric Poupon,&nbsp;Vincent Rat,&nbsp;Óscar Rojas,&nbsp;Céline Ruelle,&nbsp;Pierre Sallot,&nbsp;Daniel Scotson,&nbsp;Christian Semmler,&nbsp;Serge Selezneff,&nbsp;Sophie Senani de Monredon,&nbsp;Kentaro Shinoda,&nbsp;Pawel Sokolowski,&nbsp;Uwe Schulz,&nbsp;Moussa Tembely,&nbsp;Filofteia-Laura Toma,&nbsp;Pascal Tristant,&nbsp;Thibaut Van Hoof,&nbsp;Armelle Vardelle,&nbsp;Robert Vassen,&nbsp;Scott Wilson,&nbsp;Ping Xiao,&nbsp;Guan-Jun Yang,&nbsp;Shuo Yin,&nbsp;Stephen Yue,&nbsp;Tianqi Zhu","doi":"10.1007/s11666-026-02276-5","DOIUrl":"10.1007/s11666-026-02276-5","url":null,"abstract":"<p>A decade after the JTST released its roadmap on thermal spray, which emphasized the processes, coatings, and applications of thermal spray, the current roadmap shifts its focus to spray processes and vapor deposition methods aimed at decarbonizing aviation. Academic and industry experts are collaborating to share insights on how thermal spray and vapor deposition techniques and coatings can advance sustainable aviation and the necessary research to overcome associated challenges. This roadmap can serve as a valuable reference point for researchers aiming to understand the field’s trajectory and identify critical gaps to address.</p>","PeriodicalId":679,"journal":{"name":"Journal of Thermal Spray Technology","volume":"35 6","pages":"2099 - 2200"},"PeriodicalIF":3.4,"publicationDate":"2026-07-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s11666-026-02276-5.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148807510","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Corrosion Behavior of Cold-Sprayed 316L Coatings: Effects of Deposition Temperature and Surface Condition","authors":"Brenda Juliet Martins Freitas,&nbsp;Vinicius Gustavo da Cruz,&nbsp;Alexandre Romão Costa Nascimento,&nbsp;Luc Pouliot,&nbsp;Bruna Fernanda Batistão,&nbsp;Eduardo Campos Payao da Silva,&nbsp;Piter Gargarella,&nbsp;Claudemiro Bolfarini,&nbsp;Guilherme Yuuki Koga","doi":"10.1007/s11666-026-02299-y","DOIUrl":"10.1007/s11666-026-02299-y","url":null,"abstract":"<div><p>The passivation behavior of cold-sprayed 316L stainless steel coatings deposited onto SAE 1020 carbon steel was investigated with particular emphasis on the influence of surface condition and deposition temperature. Coatings produced at gas temperatures of 650-825 °C exhibited thicknesses of ~ 450-520 <i>µ</i>m and porosity levels of ~ 5-7 vol.%, with microstructures characterized by interparticle boundaries and incomplete bonding typical of cold-sprayed deposits. Electrochemical performance was evaluated in 0.6 M NaCl solution using open circuit potential (OCP), electrochemical impedance spectroscopy (EIS), and cyclic potentiodynamic polarization (CPP). In the polished condition, the coatings consistently exhibited a shift toward more noble OCP values compared to both the as-sprayed state and the SAE 1020 substrate, indicating enhanced surface stability. Despite moderate polarization resistance and the presence of microstructural heterogeneities, EIS results revealed capacitive responses associated with passive-like surface films. Cyclic polarization further demonstrated that polished coatings are capable of sustaining anodic polarization without abrupt current increase, in contrast to the active behavior of the substrate, and in some cases showed evidence of repassivation. These findings indicate that surface finishing plays a critical role in stabilizing passive-like behavior, even in the presence of residual porosity. Overall, the results demonstrate that polished cold-sprayed 316L coatings effectively promote passivation and significantly improve the corrosion resistance of carbon steel substrates in chloride-containing environments. </p></div>","PeriodicalId":679,"journal":{"name":"Journal of Thermal Spray Technology","volume":"35 7","pages":"2940 - 2955"},"PeriodicalIF":3.4,"publicationDate":"2026-07-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s11666-026-02299-y.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149310703","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Special Issue on Intelligent Coating Processes","authors":"Alejandro Vargas-Uscategui,&nbsp;Ali Dolatabadi,&nbsp;Anssi Laukkanen","doi":"10.1007/s11666-026-02301-7","DOIUrl":"10.1007/s11666-026-02301-7","url":null,"abstract":"","PeriodicalId":679,"journal":{"name":"Journal of Thermal Spray Technology","volume":"35 6","pages":"2201 - 2203"},"PeriodicalIF":3.4,"publicationDate":"2026-07-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148807511","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Microstructure and Synergistic Enhancement of Hardness, Wear Resistance, and Toughness in Plasma Sprayed Iron-Based Composite Coatings","authors":"Xiang Gao,&nbsp;Jian Zhang,&nbsp;Hongxuan Chen,&nbsp;Yun Chen,&nbsp;Xiaotong Pang","doi":"10.1007/s11666-026-02303-5","DOIUrl":"10.1007/s11666-026-02303-5","url":null,"abstract":"<div><p>Although iron-based composite coatings are widely used to improve the surface performance of structural steels, simultaneously achieving high hardness, wear resistance, and impact toughness remains a considerable challenge due to inherent strength-toughness trade-offs. In this work, a Fe-Mo-V-B-C alloy powder was designed and synthesized by gas atomization, and subsequently deposited on Q235 steel substrates via plasma spraying to fabricate iron-based composite coatings. Microstructural characterization indicates that the coating is composed of a martensitic matrix reinforced by petal-like VC and blocky to skeleton Mo₂B eutectic phases, with volume fractions of 16.5 and 41.6%, respectively, uniformly distributed throughout the coating. The synergistic reinforcement of these hard phases results in a Vickers hardness of 991HV_0.5, a low friction coefficient of 0.409, and a reduced wear loss of 4.5 mg. Wear is dominated by subsurface-crack-induced spalling, combining abrasive and adhesive mechanisms. Importantly, the coating exhibits excellent fracture toughness (50.4 MPa·m^1/2) and impact toughness (111.63 J/cm²). Fractographic analysis reveals shallow dimples and tearing ridges, characteristic of ductile fracture, where the skeleton Mo₂B eutectic structure enhances toughness by deflecting cracks and prolonging their propagation paths. This work provides a feasible materials design strategy for iron-based coatings that reconcile hardness, wear resistance, and impact toughness, offering theoretical guidance for engineering applications requiring severe wear and impact conditions.</p></div>","PeriodicalId":679,"journal":{"name":"Journal of Thermal Spray Technology","volume":"35 7","pages":"3366 - 3380"},"PeriodicalIF":3.4,"publicationDate":"2026-07-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149310719","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Investigation of Criteria for Wire-Arc Spraying Process Stability","authors":"K. Bobzin,&nbsp;Thorsten Papenbrock,&nbsp;H. Heinemann,&nbsp;M. Erck,&nbsp;Marcian Seeger,&nbsp;L. M. Johann","doi":"10.1007/s11666-026-02282-7","DOIUrl":"10.1007/s11666-026-02282-7","url":null,"abstract":"<div><p>Wire-Arc Spraying (WAS) is an economical and widely used thermal spray process. Applications include corrosion protection coatings on offshore wind power plants. While WAS is cost-efficient and technologically well-developed, the high process complexity results in a lack of physics-based models. The process is characterized by fluctuations of an electric arc which moves along the wire tips. Regular, periodic process fluctuations, caused by droplet detachment and the corresponding arc movement, are intrinsic to WAS. However, irregular, aperiodic fluctuations, such as arc interruptions, indicate an unstable process and must be avoided. These irregular fluctuations can lead to plant downtime, coating defects and therefore an increase in maintenance and quality control costs. This study employs time-series anomaly detection algorithms on WAS sensor data and introduces a novel optimization criterion, <i>σ</i>_L, which is specifically derived for thermal spraying processes for the purpose of process stability assessment. To collect the necessary time-series data, a sensor unit was set up on a WAS system. ZnAl15 wire and Fe₆₂Si₁₂B₈C₄Nb₂Mo₂Cr₁₀ cored wire were used as feedstock materials. ZnAl15 spraying included multiple experimental runs according to the design of experiment methodology. The ZnAl15 coatings were applied onto C45 steel substrate. Each sample was weighed before and after spraying to determine the deposition efficiency. Voltage and electric current in every experiment were measured at a sampling rate of 500 kHz. Fast Fourier Transformations (FFT) were calculated on the electrical resistance, which was derived by Ohm’s law. The signal analysis revealed WAS process-related fundamental frequencies in the range of 0.5-1.0 kHz, alongside frequencies at 20 kHz, which stem from the power control unit. The novel criterion <i>σ</i>_L is calculated on the first range of frequencies. The fact that <i>σ</i>_L shows low sensitivity to regular process fluctuations makes it superior to conventional metrics. By generalized linear modeling, <i>σ</i>_L as well as the deposition efficiency were fitted to the investigated parameters. Combining <i>σ</i>_L and known anomaly detection algorithms such as thresholding and <i>k</i>-means allows for the detection of detrimental fluctuations and process interruptions.</p></div>","PeriodicalId":679,"journal":{"name":"Journal of Thermal Spray Technology","volume":"35 6","pages":"2283 - 2293"},"PeriodicalIF":3.4,"publicationDate":"2026-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148807379","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Numerical Model of a Hydrogen-Fueled HVOF Thermal Spray Process","authors":"Benedikt Biller,&nbsp;Alexander Bußmann,&nbsp;Olivier Messe,&nbsp;Marcus Giglmaier,&nbsp;Nikolaus A. Adams","doi":"10.1007/s11666-026-02285-4","DOIUrl":"10.1007/s11666-026-02285-4","url":null,"abstract":"<div><p>The present study introduces and validates a comprehensive numerical model for hydrogen-fueled high-velocity oxygen-fuel (HVOF) spraying of tungsten carbide-cobalt-chromium (WC-Co-Cr) powder. We conduct three-dimensional (3D), two-way coupled simulations of the reactive, particle-laden flow within the DJ2600 thermal spray gun and its supersonic exhaust jet. The model incorporates the real nozzle geometry, applies the eddy-dissipation concept (EDC) as a finite-rate chemistry approach for hydrogen combustion, and uses an explicit algebraic Reynolds stress model (EARSM) for turbulent scales. Consequently, our simulations enable a precise analysis of flame dynamics by revealing unprecedented levels of flow field detail in the nozzle’s convergent section. We find that the interaction of fuel, oxidizer, and cooling air streams produces diverse, three-dimensional flame shapes. Furthermore, we compare the standard particle modeling approach from literature with an enhanced approach that accounts for rarefied flow at the particle scale, viscous heating in the boundary layers around particles, and temperature-dependent particle heat capacities. Our results demonstrate that including these phenomena is critical for correctly predicting particle impact properties. Finally, we analyze particle states both in flight and upon impact on the target surface.</p></div>","PeriodicalId":679,"journal":{"name":"Journal of Thermal Spray Technology","volume":"35 7","pages":"3306 - 3329"},"PeriodicalIF":3.4,"publicationDate":"2026-07-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s11666-026-02285-4.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149310186","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Machine Learning-Assisted Study of Bond Coat Deposition via Spot Spray in Internal Diameter APS","authors":"Bo Liu,&nbsp;Wen Huang,&nbsp;Qi Zhang,&nbsp;Qing He","doi":"10.1007/s11666-026-02288-1","DOIUrl":"10.1007/s11666-026-02288-1","url":null,"abstract":"<div><p>Internal diameter atmospheric plasma spraying (ID-APS) is an effective technique for coating confined and curved internal surfaces, especially within the narrow internal passages of aerospace, energy, and automotive components where conventional thermal spray methods are unsuitable. However, the specialized structural constraints of the internal diameter torch nozzle lead to intricate plasma-substrate interactions. Compared to external surface thermal spraying, research on ID-APS remains limited, and this inherent complexity impedes systematic modeling and quantitative characterization. In this study, an internal diameter plasma torch was employed for spot spraying to extract key bond coat spray spot properties, including deposition efficiency and the geometric profiles characterized by maximum height and full width at half maximum. Subsequently, statistical association analysis was performed to examine the relationships between the input spray parameters and the spot properties. Utilizing a dataset derived from a systematic experimental design, machine learning-based regression models were established to accurately predict these spot properties in ID-APS, and an attribution analysis was conducted to identify the most influential parameters and clarify their specific impacts on bond coat deposition behavior. This study establishes a systematic, data-driven framework for ID-APS that elucidates the relationships between spray parameters and the resulting spot properties, enables predictive modeling, and offers a generalizable methodology for analyzing governing factors in powder deposition and related coating processes.</p></div>","PeriodicalId":679,"journal":{"name":"Journal of Thermal Spray Technology","volume":"35 7","pages":"3173 - 3195"},"PeriodicalIF":3.4,"publicationDate":"2026-07-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149310187","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of Al and Ni Doping on the Microstructure and High-Temperature Properties of Laser Cladding Cobalt-Based Alloy Coatings","authors":"Ji Zhou,&nbsp;Ruohui Shuai,&nbsp;Jikai Yang,&nbsp;Liyan Lou,&nbsp;Yi Liu,&nbsp;Junhao Lu,&nbsp;Zhihai Cai,&nbsp;Jing Li,&nbsp;Zhiguo Xing,&nbsp;Haidou Wang,&nbsp;Chengxin Li","doi":"10.1007/s11666-026-02283-6","DOIUrl":"10.1007/s11666-026-02283-6","url":null,"abstract":"<div><p>To extend hot work roll life, this study laser-clad Al/Ni-doped cobalt-based alloy coatings, systematically investigating Al/Ni doping effects on their microstructure, phase composition, microhardness, hot hardness, and 800 °C high-temperature tribological behavior.The results showed that the Al/Ni-doped Co-based coatings formed a metallurgical bond with the substrate, presenting a dense and homogeneous microstructure without porosity or cracks, and were mainly composed of <i>γ</i>-Co, M₂₃C₆, and M₇C₃ phases. Al/Ni addition promoted the precipitation of Al-enriched strengthening phases and refined the microstructure. Benefiting from the combined effects of solid solution, dispersion, and grain refinement strengthening, the Co21-AlNi coating’s microhardness significantly increased from 356.9 to 385 HV_0.2, retaining 214 HV_0.2 at 800 °C (superior to 162 HV_0.2 of Co21 coating and 34 HV_0.2 of the substrate). Additionally, the formation of a dense, adherent composite oxide film (enriched with Cr₂O₃, Co₃O₄, CoCr₂O₄, and CoAl₂O₄) and dispersed hard phases significantly improved the Co21-AlNi coating’s wear resistance and friction reduction at 800 °C, with a friction coefficient of ~ 0.39 and a wear volume only 8.1% of the substrate. The dominant wear mechanism was oxidative wear accompanied by slight abrasive and adhesive wear. This study provides a theoretical basis for developing high-performance, durable coatings for hot-rolled components.</p></div>","PeriodicalId":679,"journal":{"name":"Journal of Thermal Spray Technology","volume":"35 7","pages":"2993 - 3007"},"PeriodicalIF":3.4,"publicationDate":"2026-07-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149310184","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Nozzle Geometry Optimization for Aerosol Deposition by 3D Computational Fluid Dynamics Simulations","authors":"Julio Gutiérrez de Frutos,&nbsp;Andreas Elsenberg,&nbsp;Luca Bachnick,&nbsp;Frank Gärtner,&nbsp;Thomas Klassen","doi":"10.1007/s11666-026-02278-3","DOIUrl":"10.1007/s11666-026-02278-3","url":null,"abstract":"<div><p>In aerosol deposition, fine ceramic powders in sizes of less than typically 5 μm are deposited as a coating at room temperature. Aerosol deposition must be performed under a vacuum to apply such fine powders and avoid bow shock effects. According to experimental results, coating formation by aerosol deposition only occurs if particle velocities exceed a material-specific threshold velocity. Thus, knowledge of attained particle velocities over acceleration in the nozzle and under the expansion into a vacuum is essential for deriving conditions for successful deposition. In the present study, 3D CFD simulations were used to investigate the key geometric variables in particle acceleration. Three different nozzle geometries were investigated: a converging nozzle, a converging–diverging nozzle, and a converging nozzle followed by a constant cross section toward the exit. In addition, these three nozzle geometries were optimized to maximize the particle impact velocity. The results show that the converging–diverging nozzle supplies the highest particle velocities within this comparison. By the design of optimization, the particle velocities can be improved for all the geometry types. The most promising geometry from the CFD optimization was manufactured and compared to the original one, providing a gain in experimentally measured particle velocity of 24%.</p></div>","PeriodicalId":679,"journal":{"name":"Journal of Thermal Spray Technology","volume":"35 7","pages":"2827 - 2851"},"PeriodicalIF":3.4,"publicationDate":"2026-07-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s11666-026-02278-3.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149310185","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evolution of Microstructure, Strength, and Ductility in 3D-Printed Low-Pressure Cold Spray Copper: Effects of Process Gas, Build Strategy, and Post-Deposition Heat Treatment","authors":"Niloofar Eftekhari,&nbsp;Ali R. Shams,&nbsp;Reza Hirmand,&nbsp;Hamid Jahed","doi":"10.1007/s11666-026-02291-6","DOIUrl":"10.1007/s11666-026-02291-6","url":null,"abstract":"<div><p>This study investigates the impact of N₂ and He process gases, along with heat treatment, on the microstructure and mechanical properties of cold-sprayed 3D-printed pure Cu using a low-pressure system. Microstructural analysis was conducted using XRD, optical microscopy, and EBSD, while hardness and tensile tests assessed mechanical performance. He-assisted deposition achieved higher efficiency due to increased particle velocity. However, because N₂ processing required more passes to reach the same thickness, enhanced cumulative peening led to greater plastic deformation, higher dislocation density, reduced porosity, and increased microhardness (112.19 ± 6.3 HV, compared to 87.17 ± 13.12 HV for He). Thus, property differences reflect the combined effects of impact conditions and build strategy rather than a gas-only influence. Both as-sprayed deposits exhibited brittle behavior with limited ductility. Heat treatments at 500 and 700 °C for 4 h promoted recrystallization and grain growth, with more pronounced effects at 700 °C. He-processed samples showed higher recrystallization temperatures and finer grain structures post-annealing. While 500 °C treatment partially healed interfaces, 700 °C eliminated most unbonded regions and introduced spheroidized voids. After heat treatment at 700 °C, the ultimate tensile strength improved to 213 (N₂) and 193 MPa (He), and elongation increased to 28 and 25%, respectively, up from &lt; 0.2% in the as-sprayed condition. Notably, the heat-treated N₂ samples exhibited improved metallurgical bonding, slightly outperforming those processed with He. Despite the enhancements, the mechanical properties remained inferior to those of cold-rolled and annealed bulk copper. Nonetheless, the results highlight that N₂, when used with optimized parameters and heat treatment, offers a cost-effective alternative to He for cold spray applications. To further emphasize the role of in-process densification induced by the peening effect, particle deposition using N₂ and He was simulated using the material point method. The results show that the accumulation of plastic strain is greater in the N₂-deposited particles than in the He-deposited particles due to the enhanced peening effect associated with N₂ deposition.</p></div>","PeriodicalId":679,"journal":{"name":"Journal of Thermal Spray Technology","volume":"35 7","pages":"2864 - 2888"},"PeriodicalIF":3.4,"publicationDate":"2026-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149310454","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}