{"title":"Effects of heat input on microstructure evolution and corrosion resistance of underwater laser cladding high-strength low-alloy steel coating","authors":"Qi Cheng , Ning Guo , Zhenyu Xue , Hao Chen , Junhui Tong , Yuchao Ding , Yunlong Fu , Guanchen Zhou","doi":"10.1016/j.matchar.2024.114498","DOIUrl":"10.1016/j.matchar.2024.114498","url":null,"abstract":"<div><div>The effects of heat input on the microstructure evolution and corrosion resistance of the high-strength low-alloy (HSLA) steel coating obtained by wire-feed underwater laser cladding were studied. Optical digital microscope, scanning electron microscope (SEM), energy dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), transmission electron microscope (TEM), electron back-scattered diffraction (EBSD), electrochemical tests, laser microscope and other characterization methods were used. As the heat input increased, the smoothness of the underwater cladding coating improved, with little changes in elemental distribution and phase composition. However, the content of acicular ferrite increased, while the amounts of lath bainite, lath martensite, and granular bainite decreased. As the heat input increased from 0.4 to 0.55 kJ/mm, the grain size increased from 25.3 to 55.9 μm, the proportion of low-angle grain boundaries rose from 61.3 % to 69.1 %, and the texture intensity of the (110) crystal plane increased from 16.22 to 23.83. Meanwhile, the dislocation density decreased from 4.9 × 10<sup>14</sup> to 4.1 × 10<sup>14</sup> m<sup>−2</sup>. These changes enhanced the corrosion resistance of underwater coating. As the heat input increased from 0.4 to 0.55 kJ/mm, the corrosion current density decreased from 2.13 × 10<sup>−5</sup> to 3.35 × 10<sup>−6</sup> A/cm<sup>2</sup>, and the corrosion potential increased from −0.823 to −0.529 V. Additionally, the depth-to-width ratio of the corrosion pits decreased from 0.255 to 0.053. This study laid the foundation for high-quality in-situ underwater repairs of ships and submarines made of high-strength steel.</div></div>","PeriodicalId":18727,"journal":{"name":"Materials Characterization","volume":"218 ","pages":"Article 114498"},"PeriodicalIF":4.8,"publicationDate":"2024-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142554771","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Xu Wang , Yunbo Xu , Jiapeng Guo , Yuan Wang , Jingyi Ren , R.D.K. Misra
{"title":"Tailoring the microstructure by prior treatment to achieve 37.6 GPa·% PSE in a room-temperature quenched and partitioned steel","authors":"Xu Wang , Yunbo Xu , Jiapeng Guo , Yuan Wang , Jingyi Ren , R.D.K. Misra","doi":"10.1016/j.matchar.2024.114497","DOIUrl":"10.1016/j.matchar.2024.114497","url":null,"abstract":"<div><div>In this work, different initial microstructures, including deformed cold-rolled structure, quenched martensite, granular bainite, and lathy bainite, were intentionally designed through cold rolling and prior treatment. Meanwhile, a novel room-temperature quenching and partitioning (RT-Q&P) process was proposed to further enhance strength-ductility combination of Cu-Ni bearing Q&P. The present study aims to investigate the influences of initial microstructures on the formation kinetics of austenite, the mechanical stability of RA, microstructure evolution, and mechanical performance in Q&P steel treated by RT-Q&P process. Compared to sample without prior treatment, samples with prior treatment showed a larger austenization degree due to more nucleation sites on martensite/bainite matrix. DICTRA simulation indicates the lathy bainite matrix with low C and low Mn is more conducive to the refinement of parent austenite, thus leading to fine and dispersive TM/A. During tensile deformation, the fine and dispersive lath-structures can effectively alleviate strain localization on the interfaces which resulted from the deformability difference between the soft and hard phases, thereby delaying crack initiation and propagation. After RT-Q&P treatment, the outstanding mechanical properties with UTS of 1152 MPa, TEL of 32.6 %, YS of 754 MPa, and PSE of 37.6 GPa·% was achieved in sample with lathy bainite matrix, far exceeding the properties of traditional Q&P steels, which was mainly attributed to higher work-hardening ability of fine and dispersive structure and sustained TRIP effect of RA.</div></div>","PeriodicalId":18727,"journal":{"name":"Materials Characterization","volume":"218 ","pages":"Article 114497"},"PeriodicalIF":4.8,"publicationDate":"2024-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142656592","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Jian Li , Tao He , Xiang-yang Du , Alexey Vereschaka , Jun-jie Zhang
{"title":"Regulating hardness homogeneity and corrosion resistance of Al-Zn-Mg-Cu alloy via ECAP combined with inter-pass aging","authors":"Jian Li , Tao He , Xiang-yang Du , Alexey Vereschaka , Jun-jie Zhang","doi":"10.1016/j.matchar.2024.114489","DOIUrl":"10.1016/j.matchar.2024.114489","url":null,"abstract":"<div><div>The novel processing strategies of Equal Channel Angular Pressing (ECAP) combined with inter-pass aging was designed, and XRD, SEM, TEM, electrochemical testing, and hardness testing were used to evaluate the relationship between microstructure and performance of alloys in this work. The results indicate that the hardness uniformity of the circular cross-section perpendicular to the extrusion direction was improved by combining ECAP with inter-pass aging, resulting in a hardness inhomogeneity factor (∼0.030) that was lower than that achieved by peak aging and double-stage aging alloys. Polarization curves and electrochemical impedance spectra show that a more negative corrosion potential and a smaller corrosion current density were possessed by the alloy, with the maximum intergranular corrosion depth (IGC) being reduced to 38 μm. Microstructure observation indicates that the improvement in hardness uniformity is due to the uniformity of grain size and the improved distribution and size of the η’ phase, which is attributed to the interaction between the pinning and shear effects of precipitates and dislocations during deformation. The enhanced corrosion resistance was attributed to an orderly combination of deformation and aging that increases the grain boundary volume and disrupts the η phase continuity within grain boundaries.</div></div>","PeriodicalId":18727,"journal":{"name":"Materials Characterization","volume":"218 ","pages":"Article 114489"},"PeriodicalIF":4.8,"publicationDate":"2024-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142554050","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Jiawan Chen , Tieshan Cao , Wei Xu , Jiahui Wu , Yebing Hu , Lamei Cao , Yue Zhang , Congqian Cheng , Jie Zhao
{"title":"Analysis of thin-wall effect mechanism based on stress rupture properties and fracture characteristics of DD10 Ni-based single-crystal alloy","authors":"Jiawan Chen , Tieshan Cao , Wei Xu , Jiahui Wu , Yebing Hu , Lamei Cao , Yue Zhang , Congqian Cheng , Jie Zhao","doi":"10.1016/j.matchar.2024.114494","DOIUrl":"10.1016/j.matchar.2024.114494","url":null,"abstract":"<div><div>The stress rupture life and fracture characteristics of DD10 nickel-based single crystal alloy with different wall thicknesses were investigated. Stress rupture tests were performed on samples with wall thicknesses of 0.8 mm and 0.5 mm at 1000 °C/200 MPa and 1150 °C / 100 MPa. According to the experimental results, the thin wall effect was observed at both 1000 °C / 200 MPa and 1150 °C / 100 MPa. XRM (X-ray microscope) results show a larger proportion of large size cracks/voids in the 0.8 mm wall samples than in the 0.5 mm wall samples. Meanwhile, the C* values are smaller in the thicker wall samples than in the thinner wall samples for the same crack length. Combining the results of XRM and C* results speculate that a longer crack length and propagation time is required to achieve unstable propagation in thicker walled samples. This is one of the important reasons for the thin-wall effect.</div></div>","PeriodicalId":18727,"journal":{"name":"Materials Characterization","volume":"218 ","pages":"Article 114494"},"PeriodicalIF":4.8,"publicationDate":"2024-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142573407","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Microstructural evolution and cyclic oxidation behavior of HVOF-sprayed NiCrSi and NiCrC coatings on T11 steel","authors":"Subbarao Medabalimi , Ajit M. Hebbale , Richa Singh , Vijay Desai , M.R. Ramesh","doi":"10.1016/j.matchar.2024.114495","DOIUrl":"10.1016/j.matchar.2024.114495","url":null,"abstract":"<div><div>This study analyzes NiCrSi and NiCrC coatings developed on low alloy ferritic stainless steel (grade T11) through the HVOF spraying technique. The coatings were characterized by their phase constitution, microstructure, cyclic oxidation behavior, and hardness. X-ray diffraction (XRD) analysis confirmed the presence of the NiCr solid solution matrix as the primary phase in both coatings. Moreover, the microstructure of the NiCrSi coating included the hard intermetallic compounds like Cr₃Si and Ni₃Si and the NiCrC coating contained the hard phases like Cr₃C₂ and Ni₃C which improved the hardness and the wear resistance of the coatings. Microhardness measurements revealed that the coatings had an average hardness of 300 ± 50 HV, significantly greater than the substrate hardness of 225 ± 25 HV. Cyclic oxidation tests were carried out at 700 °C revealed that both the coatings showed a lower weight gain than the uncoated substrate, suggesting enhanced oxidation resistance. This was because the protective oxide layers like Cr₂O₃ and SiO₂ in the NiCrSi coating and Cr₂O₃ and NiO in the NiCrC coating were formed. X-ray analysis establish ed. the presence of these oxides, which inhibited oxygen penetration through the coatings and provided additional protection against oxidation. Therefore, the study revealed that both NiCrSi and NiCrC coatings have good mechanical and oxidation resistance properties, which make them suitable for high-temperature applications where there is a need for improved durability, wear resistance, and protection against oxidation.</div></div>","PeriodicalId":18727,"journal":{"name":"Materials Characterization","volume":"218 ","pages":"Article 114495"},"PeriodicalIF":4.8,"publicationDate":"2024-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142554773","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Ang Yin , Wenliang Yu , Wenbo Li , Wenlong Zhu , Vincent Ji , Chuanhai Jiang , Chengxi Wang
{"title":"Microstructural and thermal relaxation of residual stress in dual peened TA15 titanium alloy fabricated by SLM","authors":"Ang Yin , Wenliang Yu , Wenbo Li , Wenlong Zhu , Vincent Ji , Chuanhai Jiang , Chengxi Wang","doi":"10.1016/j.matchar.2024.114496","DOIUrl":"10.1016/j.matchar.2024.114496","url":null,"abstract":"<div><div>TA15 (Ti-6Al-2Zr-1Mo-1 V) is a near-α titanium alloy widely used in aerospace applications due to its high specific strength and corrosion resistance. However, like other titanium alloys, TA15 faces significant manufacturing challenges. Selective Laser Melting (SLM), a high-precision additive manufacturing technique, enables the efficient production of complex components but also introduces issues such as tensile residual stress. This study investigates the effects of dual shot peening on the residual stress and microstructure of SLM-fabricated TA15 alloy, and analyzes the thermal relaxation behavior post-peening. The results indicate that shot peening induces a compressive residual stress (CRS) field near the material surface and significantly refines the grains in the deformed layer, resulting in the formation of nanocrystals. The introduction of low-intensity ceramic shots in dual shot peening effectively improves the surface quality and enhances CRS, although it has minimal impact on grain size and microstrain. Using the ZWA model, the activation energy for thermal relaxation of residual stress and microstrain was determined, revealing that their relaxation behavior is controlled by thermally activated diffusion of point defects, especially vacancies. Post-thermal exposure, extensive dislocation annihilation and grain growth were observed in the deformed layer, with recrystallized grain size increasing with annealing temperature and depth.</div></div>","PeriodicalId":18727,"journal":{"name":"Materials Characterization","volume":"218 ","pages":"Article 114496"},"PeriodicalIF":4.8,"publicationDate":"2024-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142554048","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Andrea Farkas , Gergely Farkas , Patrik Dobroň , Jozef Veselý , Shin-ichi Inoue , Yoshihito Kawamura , Kristián Máthis , Daria Drozdenko
{"title":"Microstructure and thermal stability of MgZnYAl alloy containing cluster-arranged nanoplates (CANaPs)","authors":"Andrea Farkas , Gergely Farkas , Patrik Dobroň , Jozef Veselý , Shin-ichi Inoue , Yoshihito Kawamura , Kristián Máthis , Daria Drozdenko","doi":"10.1016/j.matchar.2024.114492","DOIUrl":"10.1016/j.matchar.2024.114492","url":null,"abstract":"<div><div>The thermal stability of the microstructure of Mg - 0.9 % Zn - 2.05 % Y - 0.15 % Al (at.%) alloy prepared by conventional extrusion (CE) from cast ingot and rapidly solidified (RS) ribbon consolidation method has been investigated by scanning and transmission electron microscopy. It is shown that in the initial state, although both microstructures consist of small recrystallized and large non-recrystallized grains, the distribution and morphology of the solute-enriched phases are strongly influenced by the processing route. Particularly, the RS alloy mainly contains fine homogeneously distributed cluster-arranged nanoplates (CANaPs), while the CE alloy is characterized by larger solute-enriched phases (incl. CANaPs and LPSO fractions) together with individual cluster-arranged layers (CALs) and/or thin CANaPs. Differences in the size and distribution of solute-enriched phases naturally affect the recrystallization dynamics during post-processing heat treatment. Nevertheless, both types of material exhibited exceptionally high thermal stability up to 300 °C, which significantly exceeds the values reported for conventional Mg alloy systems.</div></div>","PeriodicalId":18727,"journal":{"name":"Materials Characterization","volume":"218 ","pages":"Article 114492"},"PeriodicalIF":4.8,"publicationDate":"2024-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142578820","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Xiaochen Wu , Ruixiao Zheng , Lu Li , Hao Xu , Peihang Zhao , Chaoli Ma
{"title":"Damage mechanism identification and failure behavior of 2D needle-punched SiCf/SiC composites based on acoustic emission and digital image correlation","authors":"Xiaochen Wu , Ruixiao Zheng , Lu Li , Hao Xu , Peihang Zhao , Chaoli Ma","doi":"10.1016/j.matchar.2024.114491","DOIUrl":"10.1016/j.matchar.2024.114491","url":null,"abstract":"<div><div>In order to improve the reliability of damage analysis for SiC<sub>f</sub>/SiC composites, an identification method of damage mechanism was established by combining in-situ acoustic emission (AE) and digital image correlation (DIC). The corresponding failure behavior of 2D needle-punched SiC<sub>f</sub>/SiC composites during ambient-temperature tensile test was investigated in detail. Through a machine learning <em>k</em>-means algorithm, AE signals could be effectively divided into five clusters: friction and sliding, interface damage, matrix cracking, individual fiber breaks and collective fiber breaks. DIC results show that the surface strain of composites increased non-uniformly during the tensile process, and the architecture of the composites had a significant influence on the initiation and propagation of cracks. To summarize, the tensile process consisted of three stages: the elastic stage, the rapid propagation of matrix cracks, the coordinated fiber fracture within the large strain bands. The failure of composites was dominated by the limited load transferring ability of the interface.</div></div>","PeriodicalId":18727,"journal":{"name":"Materials Characterization","volume":"218 ","pages":"Article 114491"},"PeriodicalIF":4.8,"publicationDate":"2024-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142554772","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Lijuan Yan , Yanrong Sun , Yongchao Zhang , Shuai Wang , Huizhen Tang , Lei Li , Binghui Ge
{"title":"Reshaping precipitate structure and morphology in an Al-Zn-Mg-Cu alloy through dislocation-precipitate interactions","authors":"Lijuan Yan , Yanrong Sun , Yongchao Zhang , Shuai Wang , Huizhen Tang , Lei Li , Binghui Ge","doi":"10.1016/j.matchar.2024.114486","DOIUrl":"10.1016/j.matchar.2024.114486","url":null,"abstract":"<div><div>Mechanical properties of age-hardenable alloys are significantly influenced by the intricate interplay between precipitates and mobile dislocations. This study examined how dislocations interact with nanosized precipitates at the atomic scale in an under-aged Al-Zn-Mg-Cu alloy. Results revealed that precipitates hinder dislocation movement but are also sheared by them during deformation. Furthermore, the sheared precipitates experienced structural collapse and deviated from their usual evolutionary path, forming ordered but non-periodic topologically close-packed structures and altered morphologies. The discoveries provide insights into dislocation-precipitate interactions and strain-induced structural changes, which could inspire strategies to modulate precipitates with tailored microstructures and thereby improved alloy properties.</div></div>","PeriodicalId":18727,"journal":{"name":"Materials Characterization","volume":"218 ","pages":"Article 114486"},"PeriodicalIF":4.8,"publicationDate":"2024-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142526227","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Elevated-temperature performances of Al-Si-Cu casting alloys for cylinder head applications","authors":"Peng Hu , Lei Pan , X.-Grant Chen","doi":"10.1016/j.matchar.2024.114484","DOIUrl":"10.1016/j.matchar.2024.114484","url":null,"abstract":"<div><div>In this study, high-temperature properties of two newly developed Al-Si-Cu alloys (2Cu and 3.5Cu alloys) were investigated and compared to the commercial-grade A356 + 0.5Cu alloy (R alloy). 3.5Cu alloy exhibited the highest strength, outperforming R alloy by over 50 MPa at room temperature and by more than 20 MPa at elevated temperatures in ultimate tensile strength. However, R alloy demonstrated three to four times higher elongation than 3.5Cu alloy at room temperature, though this difference diminished at high temperatures. The minimum creep rate of 3.5Cu alloy was 2.4 times lower than that of 2Cu alloy and 14.5 times lower than that of R alloy, showing the superior creep resistance. Under low cycle fatigue loadings, the fatigue lifetimes of R and 2Cu alloys were similar, and slightly longer than that of 3.5Cu alloy. Conversely, in the high cycle fatigue regime, 3.5Cu alloy exhibited the highest fatigue resistance, followed by 2Cu and R alloys. The superior high-temperature performances of 3.5Cu alloy were attributed to the enhanced thermal stability of θ' precipitates compared to β' precipitates in R alloy, as confirmed during long-term thermal exposures at 250 and 300 °C. These findings suggest that 3.5Cu alloy is a promising candidate to replace the traditional A356 + 0.5Cu alloy for cylinder head applications.</div></div>","PeriodicalId":18727,"journal":{"name":"Materials Characterization","volume":"218 ","pages":"Article 114484"},"PeriodicalIF":4.8,"publicationDate":"2024-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142526230","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}