Materials Characterization最新文献_第4页

Microstructures and mechanical behaviors of a directional lamellar Ti-48Al-2Cr-2Nb alloy produced by laser additive manufacturing 激光快速成型技术生产的定向片状 Ti-48Al-2Cr-2Nb 合金的微观结构和力学行为

IF 4.8 2区材料科学

Materials Characterization Pub Date : 2024-10-18 DOI: 10.1016/j.matchar.2024.114470

{"title":"Microstructures and mechanical behaviors of a directional lamellar Ti-48Al-2Cr-2Nb alloy produced by laser additive manufacturing","authors":"","doi":"10.1016/j.matchar.2024.114470","DOIUrl":"10.1016/j.matchar.2024.114470","url":null,"abstract":"<div><div>Extremely large thermal gradient is considered as a unique characteristic of additive manufacturing, which can be utilized to fabricate directionally solidified alloys. In this study, we successfully fabricated a bulk Ti-48Al-2Cr-2Nb alloy with directional solidified features by the approach of direct laser deposition. The microstructural characterizations revealed that our additively manufactured (AMed) alloy was dominantly featured by a directional α<sub>2</sub>/γ lamellar microstructure. Moreover, there occurs an intriguing phenomenon that the orientation relationship between α<sub>2</sub> and γ lamellae appears a slight deviation from the well-known Blackburn relationship, which was seldom observed in previous reports. Additionally, some amounts of β<sub>o</sub> and C14-type laves phases also formed and dispersed in the lamellar microstructure. Mechanical investigations indicate that the AMed alloy achieved an improvement in yield strength at room temperature. Moreover, its yield strength can remain 630 MPa at 800 °C, comparable to the value at room temperature, and only a slight decrease occurred when the temperature was increased to 900 °C, which is superior to that of the cast one. Then, the related strengthening mechanisms were discussed based on the directional lamellar features and the particularity in orientation relationship.</div></div>","PeriodicalId":18727,"journal":{"name":"Materials Characterization","volume":null,"pages":null},"PeriodicalIF":4.8,"publicationDate":"2024-10-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142526368","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}

引用次数: 0

In-situ study the crack initiation mechanism of P92 steel under high-temperature three-point bending fatigue process 高温三点弯曲疲劳过程下 P92 钢裂纹萌发机制的原位研究

IF 4.8 2区材料科学

Materials Characterization Pub Date : 2024-10-17 DOI: 10.1016/j.matchar.2024.114447

{"title":"In-situ study the crack initiation mechanism of P92 steel under high-temperature three-point bending fatigue process","authors":"","doi":"10.1016/j.matchar.2024.114447","DOIUrl":"10.1016/j.matchar.2024.114447","url":null,"abstract":"<div><div>Various prior austenite grain size (PAGS) of the P92 specimens were obtained after annealing at 950 °C for different times. In-situ three-points bending fatigue tests were carried out to study the crack initiation mechanisms from 550 °C to 650 °C. Results revealed that the microstructure with large PAGS exhibits better cracking resistance during the fatigue process, which restricts the sliding of prior austenite grain boundary (PAGB) and tends to generate large and sparse cracks. Reducing PAGS promotes the plastic deformation and leads to the fast accumulation of fatigue damage at the initial fatigue stage. Fatigue crack at 550 °C is initiated at the prefabricated notch root, which progresses along a specific route mainly due to the intracrystalline slipping mechanism. However, as the temperature increases to 650 °C, sliding of PAGB is enhanced and it mobilizes a larger region coordinating the plastic deformation, ultimately leads to the opening of the notches. Three typical crack models are established based on the evolution of microstructures both on specimen surface and interior. Moreover, a modified θ projection method is proposed trying to predict the accumulated fatigue damage, of which the physical concepts behind the θ parameters are discussed.</div></div>","PeriodicalId":18727,"journal":{"name":"Materials Characterization","volume":null,"pages":null},"PeriodicalIF":4.8,"publicationDate":"2024-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142526500","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}

引用次数: 0

Thermally insulating flexible ceramic film based on nanowire-nanosheet dual component synergistic structure with high temperature resistance at 1300 °C 基于纳米线-纳米片双组分协同结构的隔热柔性陶瓷膜，具有 1300 °C 的耐高温性能

IF 4.8 2区材料科学

Materials Characterization Pub Date : 2024-10-17 DOI: 10.1016/j.matchar.2024.114467

{"title":"Thermally insulating flexible ceramic film based on nanowire-nanosheet dual component synergistic structure with high temperature resistance at 1300 °C","authors":"","doi":"10.1016/j.matchar.2024.114467","DOIUrl":"10.1016/j.matchar.2024.114467","url":null,"abstract":"<div><div>Nanoscale ceramic films have extensive application prospects in the fields of harsh environments because of their low thermal conductivity, excellent high temperature resistance and fire-retardant. However, the practical application of ceramic film materials is always constrained by structural collapse under prolonged high temperature treatment. Herein, silicon nitride nanowire‑calcium phosphate nanosheet (SiNNW/CHNT) film with synergistic structure is synthesized, where CHNT provides the high temperature protective layer and SiNNW endows the stable skeleton structure. Benefiting from the unique synergistic effect between SiNNW and CHNT, SiNNW/CHNT film demonstrates excellent stability and thermal insulation in high temperature environment. SiNNW/CHNT film exhibits superior high temperature stability, without significant dimensional change even after treated at 1200 °C for 74 h. Additionally, when a human hand is covered with SiNNW/CHNT thermal insulating gloves, it is not feel heat sensing under the butane blowtorch (1300 °C). This research might open up a new strategy for the fabrication of dual-component film with superior thermal structural stability and thermal protection efficiency.</div></div>","PeriodicalId":18727,"journal":{"name":"Materials Characterization","volume":null,"pages":null},"PeriodicalIF":4.8,"publicationDate":"2024-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142526499","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}

引用次数: 0

Enhanced multiple precipitation and long-term stability in AlCuMgSi(Sc) alloys with Er additions 添加 Er 后 AlCuMgSi（Sc）合金的多重析出和长期稳定性得到增强

IF 4.8 2区材料科学

Materials Characterization Pub Date : 2024-10-17 DOI: 10.1016/j.matchar.2024.114461

{"title":"Enhanced multiple precipitation and long-term stability in AlCuMgSi(Sc) alloys with Er additions","authors":"","doi":"10.1016/j.matchar.2024.114461","DOIUrl":"10.1016/j.matchar.2024.114461","url":null,"abstract":"<div><div>The precipitate evolution and microstructure stability of AlCuMgSiSc alloys with Er additions were intentionally investigated. It reveals that the Cu-containing metastable precipitates (rod-liked Q′ and lath-liked L precipitates) are promoted and achieved highest tensile strength of ∼441.3 MPa through precipitation strengthening after aging at 12 h in AlCuMgSiErSc alloy. Meanwhile, the AlCuMgSiErSc alloy shows approximately ∼6.9 % and ∼ 10.8 % higher UTS (27.7 MPa) and YS (34.1 MPa) than AlCuMgSiSc alloy after severe over aging for 150 h, respectively. Surprisingly, the σ-Al<sub>5</sub>Cu<sub>6</sub>Mg<sub>2</sub> precipitates are rarely observed in AlCuMgSiErSc alloy indicating that the formation of σ-Al<sub>5</sub>Cu<sub>6</sub>Mg<sub>2</sub> is inhibited. The excellent thermal stability can be explained by the high density of Q′ precipitates with hybrid structures and L precipitates. Moreover, Er solute atoms preferentially segregate at the interface of the Q′ precipitates and enrich the θ' precipitate, which inhibits the diffusion of solute atoms and stabilizes the coarsening of precipitates. This work may provide a strategy for designing Al<img>Cu series alloys with thermally stable microstructures.</div></div>","PeriodicalId":18727,"journal":{"name":"Materials Characterization","volume":null,"pages":null},"PeriodicalIF":4.8,"publicationDate":"2024-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142526372","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}

引用次数: 0

Effect of mechanical vibration on microstructure and performance of Fe-based composite coatings fabricated by underwater laser deposition technology 机械振动对水下激光沉积技术制造的铁基复合涂层微观结构和性能的影响

IF 4.8 2区材料科学

Materials Characterization Pub Date : 2024-10-16 DOI: 10.1016/j.matchar.2024.114466

{"title":"Effect of mechanical vibration on microstructure and performance of Fe-based composite coatings fabricated by underwater laser deposition technology","authors":"","doi":"10.1016/j.matchar.2024.114466","DOIUrl":"10.1016/j.matchar.2024.114466","url":null,"abstract":"<div><div>To solve the problem of the uneven composition and poor performance caused by water environment during the underwater laser deposition process, the mechanical vibration assisted underwater laser deposition technology was innovatively proposed, and Fe-based composite layer was successfully prepared. The microstructure, grain type and properties of Fe-based composite layer with and without mechanical vibration were studied and compared. The results showed that the mechanical vibration broke the grain and promoted the formation of more nuclei, which reduced the average grain size by 13.48 %. The solute located in the grain gap was transferred to the liquid molten pool by mechanical vibration, which reduced the Ti content in the intergranular precipitated phase Fe<sub>2</sub>Ti and made the Fe<sub>2</sub>Ti from coarse continuous distribution to fine discontinuous distribution. Additionally, the mechanisms of mechanical vibration promoting the performance of the composite were analyzed comprehensively. Compared with the composite without mechanical vibration, the composite with mechanical vibration had good corrosion resistance after 30 days of immersion, and the tribo-corrosion resistance was also improved. With the aid of mechanical vibration, the ultimate tensile strength and elongation of the composite were increased by 11.30 % and 22.08 %, respectively, due to the formation of recrystallized grains, high density high-angle grain boundaries, and fine intergranular precipitate. This study was expected to provide a new way to regulate the microstructure and properties of the underwater laser deposition layer, and promote the application of underwater laser deposition technology in marine engineering equipment.</div></div>","PeriodicalId":18727,"journal":{"name":"Materials Characterization","volume":null,"pages":null},"PeriodicalIF":4.8,"publicationDate":"2024-10-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142526375","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}

引用次数: 0

Evolution of microstructure and properties of nanocrystalline NiCo alloy under high-energy laser shock 纳米晶镍钴合金在高能激光冲击下的微观结构和性能演变

IF 4.8 2区材料科学

Materials Characterization Pub Date : 2024-10-16 DOI: 10.1016/j.matchar.2024.114464

{"title":"Evolution of microstructure and properties of nanocrystalline NiCo alloy under high-energy laser shock","authors":"","doi":"10.1016/j.matchar.2024.114464","DOIUrl":"10.1016/j.matchar.2024.114464","url":null,"abstract":"<div><div>In this study, nanocrystalline NiCo alloy was prepared through electrodeposition and subjected to high-energy laser shock (HELS) treatment to investigate the influence of laser shock on the microstructures and properties. An analysis of phase composition, microstructural evolution, texture evolution, and hardness was conducted. The results indicated that under HELS, there was no change in phase composition, while there was a slight reduction in grain size, as well as in the quantities of Low-angle grain boundaries (LAGBs) and twin boundaries (TBs). The texture evolution revealed that HELS led to a more uniform overall texture due to grain boundary (GB) mediate deformation mechanisms, along with the generation of a significant amount of 9R phases, causing a shift in texture orientation from (110) to (100). The internal structure of nanocrystalline NiCo showed an accumulation of numerous dislocations post-laser shock, with randomly oriented dislocations interacting to form Lomer-Cottrell Locks (L-C Locks) and 9R phases. Additionally, interactions with large stacking faults (SFs) also resulted in their dissociation into multiple 9R phases. The hardness enhancement was mainly attributed to the accumulation of dislocations within the grain and the generation of a significant quantity of 9R phases.</div></div>","PeriodicalId":18727,"journal":{"name":"Materials Characterization","volume":null,"pages":null},"PeriodicalIF":4.8,"publicationDate":"2024-10-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142573409","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}

引用次数: 0

Influence of heat input on pinless friction stir spot welding of aluminum‑copper dissimilar materials 输入热量对铝铜异种材料无针摩擦搅拌点焊的影响

IF 4.8 2区材料科学

Materials Characterization Pub Date : 2024-10-16 DOI: 10.1016/j.matchar.2024.114456

{"title":"Influence of heat input on pinless friction stir spot welding of aluminum‑copper dissimilar materials","authors":"","doi":"10.1016/j.matchar.2024.114456","DOIUrl":"10.1016/j.matchar.2024.114456","url":null,"abstract":"<div><div>The composite structures of aluminum/copper dissimilar materials hold significant practical value and potential in advanced technology and industrial applications. This study conducted lap welding experiments on 2 mm thick T2 copper and 1060 pure aluminum rods using the pinless friction stir spot welding process. By varying the dwelling time of the tool, the evolution behavior of the Cu<img>Al interface layer and the mechanical properties of the joints were analyzed. At low dwelling times, the heat input was relatively low, resulting in a thinner IMC layer and the best mechanical properties of the joints, with a pull-out force of 2238.2 N and a tensile strength of 28.49 MPa. The fracture modes of the joints under all parameters were brittle fractures. The connection of aluminum/copper dissimilar materials involves two processes: firstly, the diffusion bonding dominated by kinetics at the initial welding stage; and secondly, the solid-liquid instantaneous bonding dominated by thermodynamics. When the welding temperature exceeds the melting point of aluminum, the aluminum/copper interface continuously undergoes transformation-bonding-retransformation processes until the welding process is completed.</div></div>","PeriodicalId":18727,"journal":{"name":"Materials Characterization","volume":null,"pages":null},"PeriodicalIF":4.8,"publicationDate":"2024-10-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142526371","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}

引用次数: 0

Investigating the impact toughness properties and influential factors of titanium alloy joints 研究钛合金接头的冲击韧性特性和影响因素

IF 4.8 2区材料科学

Materials Characterization Pub Date : 2024-10-16 DOI: 10.1016/j.matchar.2024.114465

{"title":"Investigating the impact toughness properties and influential factors of titanium alloy joints","authors":"","doi":"10.1016/j.matchar.2024.114465","DOIUrl":"10.1016/j.matchar.2024.114465","url":null,"abstract":"<div><div>Double-sided symmetric MIG welding can significantly enhance welding efficiency for thick titanium alloys and holds promising engineering applications. However, the use of high currents and deposition rates in this process not only boosts welding efficiency but also impacts joint performance, particularly its impact toughness. In this study, the Charpy impact performance of double-sided double-arc MIG welded joints in each region was studied via oscillometric impact tests, and the main factors affecting the impact of joints were revealed. Scanning electron microscope was used to observe the fractures, and the microstructure characteristics and grain orientation of the impact crack propagation path were observed and analysed via metallurgical microscopy and EBSD. In addition, the microstructure of each region of the joint was observed via metallographic microscopy and transmission electron microscopy, which revealed the microstructure characteristics of different regions of the joint and clarified the effects of microstructure and grain orientation in different regions of the welded joint on the impact performance of each region of the double-sided, double-arc MIG welded joint. The results show that the crack initiation energy across different regions of joints typically ranges between 18 and 20 J, with minimal variations. Crack propagation plays a pivotal role in determining impact toughness, which is influenced both by microstructural features and orientation. This provides guidance for subsequent adjustments and improvements to the impact performance of the joint.</div></div>","PeriodicalId":18727,"journal":{"name":"Materials Characterization","volume":null,"pages":null},"PeriodicalIF":4.8,"publicationDate":"2024-10-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142526363","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}

引用次数: 0

A unique kind of distribution band of martensitic laths formed along {332}〈113〉 twin boundary in the Ti42Nb alloy subjected to instable deformation 受不稳定变形影响的 Ti42Nb 合金中沿 {332}〈113〉孪晶边界形成的一种独特的马氏体板条分布带

IF 4.8 2区材料科学

Materials Characterization Pub Date : 2024-10-15 DOI: 10.1016/j.matchar.2024.114460

引用次数: 0

Quantification of nanoscale precipitation in AA7050 using X-ray scattering, electron microscopy and automated particle counting techniques 利用 X 射线散射、电子显微镜和自动粒子计数技术量化 AA7050 中的纳米级沉淀

IF 4.8 2区材料科学

Materials Characterization Pub Date : 2024-10-14 DOI: 10.1016/j.matchar.2024.114457

{"title":"Quantification of nanoscale precipitation in AA7050 using X-ray scattering, electron microscopy and automated particle counting techniques","authors":"","doi":"10.1016/j.matchar.2024.114457","DOIUrl":"10.1016/j.matchar.2024.114457","url":null,"abstract":"<div><div>Material strength is dependent on several factors, including precipitation strengthening, which is the main strengthening mechanism in AA7050 aluminum alloys. These alloys contain numerous nanometer-scale precipitates that occur throughout grains and along grain boundaries when subjected to a range of heat treatment conditions. In this study, three different characterization methods were used to characterize these nanoscale precipitates: conventional scanning transmission electron microscopy (STEM); laboratory-based small-angle X-ray scattering (SAXS); and a new software analysis tool developed by Thermo Fisher Scientific: automated particle workflow (APW). Each method was used to determine average precipitate size and volume fraction of precipitation in AA7050-T7451 specimens with variable post-T7 heat treatment procedures. STEM techniques measured the average particle size as ranging from 7.6 to 17.6 nm, compared to 6.3–10.7 nm for SAXS, and 7.4–10.8 nm for APW. Volume fraction determinations varied from 0.23 to 16 %, depending on method, and were the most difficult to quantify. Significant outcomes of the current study are that SAXS and APW are the most accurate methods for determining average particle size and that future work is needed to effectively analyze precipitate volume fraction.</div></div>","PeriodicalId":18727,"journal":{"name":"Materials Characterization","volume":null,"pages":null},"PeriodicalIF":4.8,"publicationDate":"2024-10-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142526378","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}

引用次数: 0