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Laser Additive Manufacturing of 316L Stainless Steel Thin-wall Ring Parts
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作者 Yanhua Zhao Wenhao Tian +3 位作者 Jianhua Liu Dongqing Qian Wei Meng Jiaming Wang 《Fluid Dynamics & Materials Processing》 EI 2023年第2期451-470,共20页
The process parameters of laser additive manufacturing have an important influence on the forming quality of the produced items or parts.In the present work,a finite element model for simulating transient heat transfe... The process parameters of laser additive manufacturing have an important influence on the forming quality of the produced items or parts.In the present work,a finite element model for simulating transient heat transfer in such processes has been implemented using the ANSYS software,and the temperature and stress distributions related to 316L stainless steel thin-walled ring parts have been simulated and analyzed.The effect of the laser power,scanning speed,and scanning mode on temperature distribution,molten pool structure,deformation,and stress field has been studied.The simulation results show that the peak temperature,weld pool size,deformation,and residual stress increase with an increase in laser power and a decrease in the scanning speed.The scanning mode has no obvious effect on temperature distribution,deformation,and residual stress.In addition,a forming experiment was carried out.The experimental results show that the samples prepared by laser power P=800 W,V=6 mm/s,and the normal scanning method display good quality,whereas the samples prepared under other parameters have obvious defects.The experimental findings are consistent with the simulation results. 展开更多
关键词 laser additive manufacturing 316L stainless steel temperature field stress field
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Laser Additive Manufacturing on Metal Matrix Composites: A Review 被引量:9
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作者 Neng Li Wei Liu +4 位作者 Yan Wang Zijun Zhao Taiqi Yan Guohui Zhang Huaping Xiong 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2021年第3期195-210,共16页
Important progresses in the study of laser additive manufacturing on metal matrix composites(MMCs)have been made.Recent efforts and advances in additive manufacturing on 5 types of MMCs are presented and reviewed.The ... Important progresses in the study of laser additive manufacturing on metal matrix composites(MMCs)have been made.Recent efforts and advances in additive manufacturing on 5 types of MMCs are presented and reviewed.The main focus is on the material design,the combination of reinforcement and the metal matrix,the synthesis principle during the manufacturing process,and the resulted microstructures as well as properties.Thereafter,the trend of development in future is forecasted,including:Formation mechanism and reinforcement principle of strengthening phase;Material and process design to actively achieve expected performance;Innovative structure design based on the special properties of laser AM MMCs;Simulation,monitoring and optimization in the process of laser AM MMCs. 展开更多
关键词 laser additive manufacturing Metal matrix composites MICROSTRUCTURE PROPERTY
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Design for Ti-Al-V-Mo-Nb alloys for laser additive manufacturing based on a cluster model and on their microstructure and properties 被引量:6
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作者 Tian-yu Liu Zhi-hao Zhu +2 位作者 Shuang Zhang Xiao-hua Min Chuang Dong 《China Foundry》 SCIE CAS 2021年第4期424-432,共9页
In this study,α+βTi-Al-V-Mo-Nb alloys with the addition of multiple elements that are suitable for laser additive manufacturing(LAM)were designed according to a Ti-6Al-4V cluster formula.This formula can be expresse... In this study,α+βTi-Al-V-Mo-Nb alloys with the addition of multiple elements that are suitable for laser additive manufacturing(LAM)were designed according to a Ti-6Al-4V cluster formula.This formula can be expressed as 12[Al-Ti12](AlTi2)+5[Al-Ti14]((Mo,V,Nb)2Ti),in which Mo and Nb were added into the alloys partially instead of V to give alloys with nominal compositions of Ti-6.01Al-3.13V-1.43Nb,Ti-5.97Al-2.33V-2.93Mo,and Ti-5.97Al-2.33V-2.20Mo-0.71Nb(wt.%).The microstructures and mechanical properties of the as-deposited and heat-treated samples prepared via LAM were examined.The sizes of theβcolumnar grains andαlaths in the Nb-containing samples are found to be larger than those of the Ti-6Al-4V alloy,whereas Mo-or Mo/Nb-added alloys contain finer grains.It indicates that Nb gives rise to coarsenedβcolumnar grains andαlaths,while Mo significantly refines them.Furthermore,the single addition of Nb improves the elongation,whereas the single addition of Mo enhances the strength of the alloys.The simultaneous addition of Mo/Nb significantly improves the comprehensive mechanical properties of the alloys,leading to the best properties with an ultimate tensile strength of 1,070 MPa,a yield strength of 1,004 MPa,an elongation of 9%,and micro-hardness of 355 HV.The fracture modes of all the alloys are ductile-brittle mixed fracture. 展开更多
关键词 titanium alloy laser additive manufacturing cluster-plus-glue-atom model composition design microstructure mechanical properties
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Role of laser scan strategies in defect control,microstructural evolution and mechanical properties of steel matrix composites prepared by laser additive manufacturing 被引量:4
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作者 Hong-yu Chen Dong-dong Gu +5 位作者 Qing Ge Xin-yu Shi Hong-mei Zhang Rui Wang Han Zhang Konrad Kosiba 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2021年第3期462-474,共13页
Steel matrix composites(SMCs)reinforced with WC particles were fabricated via selective laser melting(SLM)by employing various laser scan strategies.A detailed relationship between the SLM strategies,defect formation,... Steel matrix composites(SMCs)reinforced with WC particles were fabricated via selective laser melting(SLM)by employing various laser scan strategies.A detailed relationship between the SLM strategies,defect formation,microstructural evolution,and mechanical properties of SMCs was established.The laser scan strategies can be manipulated to deliberately alter the thermal history of SMC during SLM processing.Particularly,the involved thermal cycling,which encompassed multiple layers,strongly affected the processing quality of SMCs.Sshaped scan sequence combined with interlayer offset and orthogonal stagger mode can effectively eliminate the metallurgical defects and retained austenite within the produced SMCs.However,due to large thermal stress,microcracks that were perpendicular to the building direction formed within the SMCs.By employing the checkerboard filling(CBF)hatching mode,the thermal stress arising during SLM can be significantly reduced,thus preventing the evolution of interlayer microcracks.The compressive properties of fabricated SMCs can be tailored at a high compressive strength(~3031.5 MPa)and fracture strain(~24.8%)by adopting the CBF hatching mode combined with the optimized scan sequence and stagger mode.This study demonstrates great feasibility in tuning the mechanical properties of SLM-fabricated SMCs without varying the set energy input,e.g.,laser power and scanning speed. 展开更多
关键词 laser additive manufacturing selective laser melting scan strategy defect control mechanical property
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Laser additive manufacturing of biodegradable Mg-based alloys for biomedical applications: A review 被引量:1
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作者 C.L.Wu W.J.Xie H.C.Man 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2022年第4期915-937,共23页
Metallic implants are widely used in internal fixation of bone fracture in surgical treatment.They are mainly used for providing mechanical support and stability during bone reunion,which usually takes a few months to... Metallic implants are widely used in internal fixation of bone fracture in surgical treatment.They are mainly used for providing mechanical support and stability during bone reunion,which usually takes a few months to complete.Conventional implants made of stainless steels,Ti-based alloys and CoCrMo alloys have been widely used for orthopedic reconstruction due to their high strength and high corrosion resistance.Such metallic implants will remain permanently inside the body after implantation,and a second surgery after bone healing is needed because the long-term presence of implant will lead to various problems.An implant removal surgery not only incurs expenditure,but also risk and psychological burden.As a consequence,studies on the development of biodegradable implants,which would degrade and disappear in vivo after bone reunion is completed,have drawn researchers’attention.In this connection,Mg-based alloys have shown great potentials as promising implant materials mainly due to their low density,inherent biocompatibility,biodegradability and mechanical properties close to those of bone.However,the high degradation rate of Mg-based implants in vivo is the biggest hurdle to overcome.Apart from materials selection,a fixation implant is ideally tailor-made in size and shape for an individual case,for best surgical outcomes.Therefore,laser additive manufacturing(LAM),with the advent of sophisticated laser systems and software,is an ideal process to solve these problems.In this paper,we reviewed the progress in LAM of biodegradable Mg-based alloys for biomedical applications.The effect of powder properties and laser processing parameter on the formability and quality was thoroughly discussed.The microstructure,phase constituents and metallurgical defects formed in the LAMed samples were delineated.The mechanical properties,corrosion resistance,biocompatibility and antibacterial properties of the LAMed samples were summarized and compared with samples fabricated by traditional processes.In addition,we have made some suggestions for advancing the knowledge in the LAM of Mg-based alloys for biomedical implants. 展开更多
关键词 laser additive manufacturing Magnesium alloys IMPLANT Biomedical applications Mechanical properties BIODEGRADABILITY
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Microstructure Evolution and Dynamic Mechanical Properties of Laser Additive Manufacturing Ti-6Al-4V Under High Strain Rate 被引量:1
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作者 Tao Wang Lei Zhu +7 位作者 Changhong Wang Mingming Liu Ning Wang Lingchao Qin Hao Wang Jianbo Lei Jie Tang Jun Wu 《Journal of Beijing Institute of Technology》 EI CAS 2020年第4期568-580,共13页
The dynamic mechanical properties of the Ti-6Al-4V(TC4)alloy prepared by laser additive manufacturing(LAM-TC4)under the high strain rate(HSR)are proposed.The dynamic compression experiments of LAM-TC4 are conducted wi... The dynamic mechanical properties of the Ti-6Al-4V(TC4)alloy prepared by laser additive manufacturing(LAM-TC4)under the high strain rate(HSR)are proposed.The dynamic compression experiments of LAM-TC4 are conducted with the split Hopkinson pressure bar(SHPB)equipment.The results show that as the strain rate increases,the widths of the adiabatic shear band(ASB),the micro-hardness,the degree of grain refinement near the ASB,and the dislocation density of grains grow gradually.Moreover,the increase of dislocation density of grains is the root factor in enhancing the yield strength of LAM-TC4.Meanwhile,the heat produced from the distortion and dislocations of grains promotes the heat softening effect favorable for the recrystallization of grains,resulting in the grain refinement of ASB.Furthermore,the contrastive analysis between LAM-TC4 and TC4 prepared by forging(F-TC4)indicates that under the HSR,the yield strength of LAM-TC4 is higher than that of F-TC4. 展开更多
关键词 laser additive manufacturing TI-6AL-4V dynamic mechanics properties MICROSTRUCTURE
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Toward understanding the microstructure characteristics,phase selection and magnetic properties of laser additive manufactured Nd-Fe-B permanent magnets
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作者 Bo Yao Nan Kang +6 位作者 Xiangyu Li Dou Li Mohamed EL Mansori Jing Chen Haiou Yang Hua Tan Xin Lin 《International Journal of Extreme Manufacturing》 SCIE EI CAS CSCD 2024年第1期277-294,共18页
Nd-Fe-B permanent magnets play a crucial role in energy conversion and electronic devices.The essential magnetic properties of Nd-Fe-B magnets,particularly coercivity and remanent magnetization,are significantly infue... Nd-Fe-B permanent magnets play a crucial role in energy conversion and electronic devices.The essential magnetic properties of Nd-Fe-B magnets,particularly coercivity and remanent magnetization,are significantly infuenced by the phase characteristics and microstructure.In this work,Nd-Fe-B magnets were manufactured using vacuum induction melting(VIM),laser directed energy deposition(LDED)and laser powder bed fusion(LPBF)technologies.Themicrostructure evolution and phase selection of Nd-Fe-B magnets were then clarified in detail.The results indicated that the solidification velocity(V)and cooling rate(R)are key factors in the phase selection.In terms of the VIM-casting Nd-Fe-B magnet,a large volume fraction of theα-Fe soft magnetic phase(39.7 vol.%)and Nd2Fe17Bxmetastable phase(34.7 vol.%)areformed due to the low R(2.3×10-1?C s-1),whereas only a minor fraction of the Nd2Fe14B hard magnetic phase(5.15 vol.%)is presented.For the LDED-processed Nd-Fe-B deposit,although the Nd2Fe14B hard magnetic phase also had a low value(3.4 vol.%)as the values of V(<10-2m s-1)and R(5.06×103?C s-1)increased,part of theα-Fe soft magnetic phase(31.7vol.%)is suppressed,and a higher volume of Nd2Fe17Bxmetastable phases(47.5 vol.%)areformed.As a result,both the VIM-casting and LDED-processed Nd-Fe-B deposits exhibited poor magnetic properties.In contrast,employing the high values of V(>10-2m s-1)and R(1.45×106?C s-1)in the LPBF process resulted in the substantial formation of the Nd2Fe14B hard magnetic phase(55.8 vol.%)directly from the liquid,while theα-Fe soft magnetic phase and Nd2Fe17Bxmetastable phase precipitation are suppressed in the LPBF-processed Nd-Fe-B magnet.Additionally,crystallographic texture analysis reveals that the LPBF-processedNd-Fe-B magnets exhibit isotropic magnetic characteristics.Consequently,the LPBF-processed Nd-Fe-B deposit,exhibiting a coercivity of 656 k A m-1,remanence of 0.79 T and maximum energy product of 71.5 k J m-3,achieved an acceptable magnetic performance,comparable to other additive manufacturing processed Nd-Fe-B magnets from MQP(Nd-lean)Nd-Fe-Bpowder. 展开更多
关键词 laser additive manufacturing(LAM) Nd-Fe-B permanent magnets numerical simulation microstructure magnetic properties
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Wire-feed laser additive manufacturing of dissimilar metals via dual molten pool interface interlocking mechanism 被引量:1
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作者 HE Yi ZHANG XiaoHan +4 位作者 ZHAO Zhe XU ShuoHeng XIA Min ZHANG Chen HU YaoWu 《Science China(Technological Sciences)》 SCIE EI CAS CSCD 2023年第4期976-986,共11页
Intermetallic compounds produced in laser additive manufacturing are the main factors restricting the joint performance of dissimilar metals.To solve this problem,a dual molten pool interface interlocking mechanism wa... Intermetallic compounds produced in laser additive manufacturing are the main factors restricting the joint performance of dissimilar metals.To solve this problem,a dual molten pool interface interlocking mechanism was proposed in this study.Based on a dual molten pool interface interlocking mechanism,the dissimilar metals,aluminum alloy and stainless steel,were produced as single-layer and multilayer samples,using the wire-feed laser additive manufacturing directed energy deposition technology.The preferred parameters for the dual molten pool interface interlocking mechanism process of the dissimilar metals,aluminum alloy and stainless steel,were obtained.The matching relationship between the interface connection of dissimilar metals and the process parameters was established.The results demonstrated excellent mechanical occlusion at the connection interface and no apparent intermetallic compound layer.Good feature size and high microhardness were observed under a laser power of 660 W,a wire feeding speed of 55 mm/s,and a platform moving speed of 10 mm/s.Molecular dynamics simulations demonstrated a faster rate of aluminum diffusion in the aluminum alloy substrate to stainless steel under the action of the initial contact force than without the initial contact force.Thus,the dual molten pool interface interlocking mechanism can effectively reduce the intermetallic compound layer when dissimilar metals are connected in the aerospace field. 展开更多
关键词 laser additive manufacturing dissimilar metals dual molten pool interface interlocking mechanism interface connection processparameters
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Direct fabrication of single-crystal-like structure using quasi-continuous-wave laser additive manufacturing 被引量:4
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作者 Hui Xiao Manping Cheng Lijun Song 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2021年第1期216-221,共6页
The synchronously periodic re-melting of molten pool was firstly introduced in additive manufacturing to promote the epitaxial growth of columnar structure using a novel quasi-continuous-wave(QCW)laser.The epitaxial g... The synchronously periodic re-melting of molten pool was firstly introduced in additive manufacturing to promote the epitaxial growth of columnar structure using a novel quasi-continuous-wave(QCW)laser.The epitaxial growth of columnar structure was intensified and the single-crystal-like sample with highly oriented "zigzag" columnar grains was produced.The modified molten-pool geometry and the synchronously high-frequency re-melting of the molten pool contribute to the formation of singlecrystal-like structure.This work reports a new route to promote the continuously epitaxial growth of dendrites for fabrication of single-crystal-like sample. 展开更多
关键词 laser additive manufacturing Nickel alloys Solidification microstructure TEXTURE Dendritic growth
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Interfacial Features of Stainless Steel/Titanium Alloy Multi-metal Fabricated by Laser Additive Manufacturing 被引量:1
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作者 Jialin Yang Xing Li +1 位作者 Hanbo Yao Yingchun Guan 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2022年第8期1357-1364,共8页
Laser additive manufacturing(LAM)is promising for fabricating multi-metallic component,but the mechanism of microstructural evolution at the interface of two metals is still needed to research further.In this study,a ... Laser additive manufacturing(LAM)is promising for fabricating multi-metallic component,but the mechanism of microstructural evolution at the interface of two metals is still needed to research further.In this study,a 316L stainless steel/Ti6Al4V alloy multi-metal was fabricated by LAM,and the mechanism of intermetallic phase transformation was deeply investigated.Results show that a strong reaction zone(SRZ)can be induced at the interface of the multi-metal.The phase constituents at the SRZ vary fromχ(Ti_(5)Fe_(17)Cr_(5))+Fe_(2)Ti+α′-Ti+β-Ti or FeTi to Fe_(2)Ti+χwhen the laser power is increased.When the scanning speed is further decreased,the thickness of the SRZ is significantly increased,andα′-Ti phase is also formed at this region besides Fe_(2)Ti andχphases.Moreover,the micro-hardness at the SRZ is increased,caused by the intermetallic phase transformation and elemental interdiffusion at the interface. 展开更多
关键词 laser additive manufacturing Stainless steel/titanium alloy Multi-metal Intermetallic phase Microstructural evolution
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Laser Additive Manufacturing of Bio-inspired Metallic Structures 被引量:5
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作者 Jiankai Yang Dongdong Gu +5 位作者 Kaijie Lin Yicha Zhang Meng Guo Luhao Yuan Han Zhang Hongmei Zhang 《Chinese Journal of Mechanical Engineering(Additive Manufacturing Frontiers)》 2022年第1期28-38,共11页
High-performance/multifunctional metallic components primarily determine the service performance of equip-ment applied in the aerospace,aviation,and automobile industries.Organisms have developed structures with speci... High-performance/multifunctional metallic components primarily determine the service performance of equip-ment applied in the aerospace,aviation,and automobile industries.Organisms have developed structures with specific properties over millions of years of natural evolution,thereby providing inspiration for the design of high-performance structures to satisfy the increasing demands of modern industries.From the perspective of manufacturing,the ability of conventional processing technologies is inadequate for fabricating these complex structural configurations.By contrast,laser additive manufacturing(AM)is an effective method for fabricating complex metallic bio-inspired structures owing to its layer-by-layer deposition advantage.Herein,recent devel-opments in the laser AM of bio-inspired cellular,plate,and truss structures,as well as the materials used in laser AM for bio-inspired printing are briefly reviewed.The organisms being imitated include butterfly,Norway spruce,mantis shrimp,beetle,and water spider,which expand the diversity of multifunctional structures for laser AM.The mechanical properties and functions of laser-AM-processed bio-inspired structures are discussed.Additionally,the challenges,possible outcomes,and directions of utilizing laser AM technology to fabricate high-performance/multifunctional metallic bio-inspired structures in the future are outlined. 展开更多
关键词 laser additive manufacturing(AM) laser powder bed fusion(LPBF) BIO-INSPIRED Biomimicry PROPERTY FUNCTIONALITY
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Ultrashort-time liquid phase sintering of high-performance fine-grain tungsten heavy alloys by laser additive manufacturing 被引量:1
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作者 Shangcheng Zhou Yao-Jian Liang +3 位作者 Yichao Zhu Benpeng Wang Lu Wang Yunfei Xue 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2021年第31期30-36,共7页
Liquid phase sintering(LPS)is a proven technique for preparing large-size tungsten heavy alloys(WHAs).However,for densification,this processing requires that the matrix of WHAs keeps melting for a long time,which simu... Liquid phase sintering(LPS)is a proven technique for preparing large-size tungsten heavy alloys(WHAs).However,for densification,this processing requires that the matrix of WHAs keeps melting for a long time,which simultaneously causes W grain coarsening that degenerates the performance.This work develops a novel ultrashort-time LPS method to form bulk high-performance fine-grain WHAs based on the principle of laser additive manufacturing(LAM).During LAM,the high-entropy alloy matrix(Al_(0.5)Cr_(0.9)FeNi_(2.5)V_(0.2))and W powders were fed simultaneously but only the matrix was melted by laser and most W particles remained solid,and the melted matrix rapidly solidified with laser moving away,producing an ultrashort-time LPS processing in the melt pool,i.e.,laser ultrashort-time liquid phase sintering(LULPS).The extreme short dwell time in liquid(-1/10,000 of conventional LPS)can effectively suppress W grain growth,obtaining a small size of 1/3 of the size in LPS WHAs.Meanwhile,strong convection in the melt pool of LULPS enables a nearly full densification in such a short sintering time.Compared with LPS WHAs,the LULPS fine-grain WHAs present a 42%higher yield strength,as well as an enhanced susceptibility to adiabatic shear banding(ASB)that is important for strong armor-piercing capability,indicating that LULPS can be a promising pathway for forming high-performance WHAs that surpass those prepared by conventional LPS. 展开更多
关键词 Tungsten heavy alloy laser additive manufacturing Liquid phase sintering
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Wire Oscillating Laser Additive Manufacturing of 2319 Aluminum Alloy: Optimization of Process Parameters, Microstructure, and Mechanical Properties 被引量:2
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作者 Xujian Cui Enyu Qi +3 位作者 Zhonggang Sun Chuanbao Jia Yong Zeng Shikai Wu 《Chinese Journal of Mechanical Engineering(Additive Manufacturing Frontiers)》 2022年第3期1-16,共16页
In this study,a wire oscillating laser additive manufacturing(O-WLAM)process was used to deposit 2319 aluminum alloy samples.The optimization of the deposition process parameters made it possible to obtain samples wit... In this study,a wire oscillating laser additive manufacturing(O-WLAM)process was used to deposit 2319 aluminum alloy samples.The optimization of the deposition process parameters made it possible to obtain samples with smooth surfaces and extremely low porosities.The effects of the deposition parameters on the formability and evolution of the microstructure and mechanical properties before and after heat treatment were studied.The oscillating laser deposition of 2319 aluminum alloy,especially the circular oscillation mode,significantly reduced the porosity and improved the process stability and formability compared with non-oscillating laser deposition.There were clear boundaries between the deposition units in the deposition state,the interior of which was dominated by columnar crystals with many rod-and point-shaped precipitates.After the heat treatment,theθphase was significantly dissolved.The residual dot-and rod-shapedθ'phases were dispersedly distributed,exhibiting an obvious precipitation-hardening effect.The samples in the as-deposited state had a tensile strength of 245–265 MPa,an elongation of approximately 12.6%,and an 87 HV microhardness.After heat treatment at 530°C for 20 h and aging at 175°C for 18 h,the tensile strength,elongation,and microhardness reached 425–440 MPa,approximately 10%,and 153 HV,respectively.The performance improved significantly without significant anisotropy.Compared with the samples produced by wire arc additive manufacturing(WAAM),the tensile strength increased by approximately 10%,and the strength and microhardness were significantly improved. 展开更多
关键词 Wire oscillating laser additive manufacturing 2319 aluminum alloy Heat treatment MICROSTRUCTURE Mechanical properties
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Effect of thermal deformation on microstructure and properties of TC18 titanium alloy produced by laser additive manufacturing
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作者 Xiao-dong Li Chang-yue Qiu +4 位作者 Yu-ting Liu Hong-fang Wang Dong-dong Zheng Yan-yan Zhu Shu-quan Zhang 《Journal of Iron and Steel Research(International)》 SCIE EI CAS CSCD 2020年第12期1476-1484,共9页
Grain boundary of α phase damaged ductility of laser melting-deposited TC18 titanium alloy and grain boundary of α phases were difficult to break by nominal heat treatment. An extra thermal deformation was introduce... Grain boundary of α phase damaged ductility of laser melting-deposited TC18 titanium alloy and grain boundary of α phases were difficult to break by nominal heat treatment. An extra thermal deformation was introduced to break the grain boundary of α phase with the improved mechanical property of TC18 titanium alloy fabricated by laser melting deposition technique.Results indicated that after thermal deformation, β grains in alloy seriously elongated. When sample was deformed at temperatures from 750 to 850 ℃, α phase exhibited both rod and irregular morphologies with discontinuous distribution at grain boundary, and the subsequent heat treatment would lead to spheroidization of the α phase. However, after deformation at 900 ℃, α phase transferred into β phase and the subsequent heat treatment would make continuous grain boundary of α phase reappear. The suitable hot deformation can effectively break the continuous grain boundary in laser melting-deposited TC18 alloy with respected improved ductility. 展开更多
关键词 laser additive manufacturing Nearβtitanium alloy Thermal deformation Heat treatment Microstructural characteristics
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Laser additive manufacturing of ductile Fe-based bulk metallic glass composite
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作者 Qingjie Li Dandan Qin +2 位作者 Yunzhuo Lu Xuemei Zhu Xing Lu 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2022年第26期148-153,共6页
Laser additive manufacturing(LAM)is a promising technology for processing bulk metallic glass(BMG)with freeform geometries or unlimited size.However,the inherently brittle Fe-based BMGs produced by LAM have always bee... Laser additive manufacturing(LAM)is a promising technology for processing bulk metallic glass(BMG)with freeform geometries or unlimited size.However,the inherently brittle Fe-based BMGs produced by LAM have always been plagued by the micro-cracking induced by the large thermal stresses during the LAM process.To solve this dilemma,316L stainless steel(SS)with excellent toughness and similar elemental composition was carefully selected as the second phase to form Fe-based BMG composites(BMGCs).The obtained Fe-based BMGCs are equipped with a heterogeneous structure,i.e.,the 316L SS phase is wrapped by the metallic glass and forms a unique"fishbone"structure with a micron-scale.Excitedly,the special structure nicely improves a plastic strain of the Fe-based BMGC with a strength of 2355 MPa to~17%,achieving a record-breaking achievement among Fe-based amorphous with critical dimensions over 1mm. 展开更多
关键词 laser additive manufacturing Metallic glass composite Crack free Stainless steel
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Microstructure and mechanical properties of laser additive manufactured novel titanium alloy after heat treatment 被引量:3
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作者 Tian-yu Liu Hong-yu Liu +4 位作者 Qian Yao Shi-bing Liu Kun Shi Zhi-yong Zhang Chong-yang Li 《China Foundry》 SCIE CAS 2021年第6期574-580,共7页
A novel α+β titanium alloy with multi-alloying addition was designed based on the cluster formula 12[Al-Ti_(12)](AlTi_(2))+5[Al-Ti_(14)](AlV_(1.2)Mo_(0.6)Nb_(0.2))which was derived from Ti-6Al-4V.The nominal composi... A novel α+β titanium alloy with multi-alloying addition was designed based on the cluster formula 12[Al-Ti_(12)](AlTi_(2))+5[Al-Ti_(14)](AlV_(1.2)Mo_(0.6)Nb_(0.2))which was derived from Ti-6Al-4V.The nominal composition of this novel alloy was determined as Ti-6.83Al-2.28V-2.14Mo-0.69Nb-6.79Zr.In this study,the novel alloy and Ti-6Al-4V alloy samples were prepared by laser additive manufacturing.The microstructure,micro-hardness,room/high temperature tensile properties of the as-deposited samples were investigated.Compared to Ti-6Al-4V,the novel alloy has much higher room and high temperature(600℃)tensile strengths,which are 1,427.5 MPa and 642.2 MPa,respectively;however,it has a much lower elongation(3.2%)at room temperature because of the finer microstructure.To improve the elongation of the novel alloy,heat treatment was used.After solution at 960℃ or 970℃ for 1 h followed by air cooling and aging at 550℃ for 4 h followed by air cooling,a unique bi-modal microstructure which contains crab-like primaryαand residual β phase is obtained,improving the compression elongation by 80.9% compared to the as-deposited samples.The novel alloy can be used as a high-temperature and high-strength candidate for laser additive manufacturing. 展开更多
关键词 laser additive manufacturing titanium alloy composition design heat treatment
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Effect of processing parameters on formability, microstructure, and micro-hardness of a novel laser additive manufactured Ti-6.38Al-3.87V-2.43Mo alloy 被引量:1
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作者 Tian-yu Liu Zhi-hao Zhu +2 位作者 Shuang Zhang Xiao-hua Min Chuang Dong 《China Foundry》 SCIE CAS 2022年第2期158-168,共11页
A novel Ti-6.38Al-3.87V-2.43Mo alloy was designed with a cluster formula of 12[Al-Ti12](V0.75Mo0.25Ti2)+4[Al-Ti12](Al3)by replacing Ti with Mo/V on the basis of the Ti-Al congruent alloy.The effects of laser power and... A novel Ti-6.38Al-3.87V-2.43Mo alloy was designed with a cluster formula of 12[Al-Ti12](V0.75Mo0.25Ti2)+4[Al-Ti12](Al3)by replacing Ti with Mo/V on the basis of the Ti-Al congruent alloy.The effects of laser power and scanning speed on the molten pool size,surface roughness,relative density,microstructure,and micro-hardness of single-track and bulk Ti-6.38Al-3.87V-2.43Mo samples prepared via laser additive manufacturing(LAM)were investigated.The results show that processing parameters significantly affect the formability,microstructure,and micro-hardness of the alloy.With decreasing laser power from 1,900 W to 1,000 W,the relative density is decreased from 99.86%to 90.91%due to the increase of lack-of-fusion;however,with increasing scanning speed,the relative density does not change significantly,but exceeds 99%.In particular,Ti-6.38Al-3.87V-2.43Mo samples of single-track and bulk exhibit a good formability under an input laser power of 1,900 W and a scanning speed of 8 mm·s_(-1),and display the lowest surface roughness(Ra=13.33μm)and the highest relative density(99.86%).Besides,the microstructure of LAM Ti-6.38Al-3.87V-2.43Mo alloy coarsens with increasing laser power or decreasing scanning speed due to the greater input energy reducing the cooling rate.The coarsening of the microstructure decreases the microhardness of the alloy. 展开更多
关键词 laser additive manufacturing composition design cluster-plus-glue-atom model MICROSTRUCTURE properties
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Study of the intrinsic mechanisms of nickel additive for grain refinement and strength enhancement of laser aided additively manufactured Ti–6Al–4V 被引量:7
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作者 Shang Sui Youxiang Chew +3 位作者 Fei Weng Chaolin Tan Zhenglin Du Guijun Bi 《International Journal of Extreme Manufacturing》 SCIE EI CAS 2022年第3期132-148,共17页
It is well-known that grain refiners can tailor the microstructure and enhance the mechanical properties of titanium alloys fabricated by additive manufacturing(AM). However, the intrinsic mechanisms of Ni addition on... It is well-known that grain refiners can tailor the microstructure and enhance the mechanical properties of titanium alloys fabricated by additive manufacturing(AM). However, the intrinsic mechanisms of Ni addition on AM-built Ti–6Al–4V alloy is not well established. This limits its industrial applications. This work systematically investigated the influence of Ni additive on Ti–6Al–4V alloy fabricated by laser aided additive manufacturing(LAAM). The results showed that Ni addition yields three key effects on the microstructural evolution of LAAM-built Ti–6Al–4V alloy.(a) Ni additive remarkably refines the prior-β grains, which is due to the widened solidification range. As the Ni addition increased from 0 to 2.5 wt. %, the major-axis length and aspect ratio of the prior-β grains reduced from over 1500 μm and 7 to 97.7 μm and1.46, respectively.(b) Ni additive can discernibly induce the formation of globular α phase,which is attributed to the enhanced concentration gradient between the β and α phases. This is the driving force of globularization according to the termination mass transfer theory. The aspect ratio of the α laths decreased from 4.14 to 2.79 as the Ni addition increased from 0 to2.5 wt. %.(c) Ni as a well-known β-stabilizer and it can remarkably increase the volume fraction of β phase. Room-temperature tensile results demonstrated an increase in mechanical strength and an almost linearly decreasing elongation with increasing Ni addition. A modified mathematical model was used to quantitatively analyze the strengthening mechanism. It was evident from the results that the α lath phase and the solid solutes contribute the most to the overall yield strength of the LAAM-built Ti–6Al–4V–x Ni alloys in this work. Furthermore, the decrease in elongation with increasing Ni addition is due to the deterioration in deformability of the β phase caused by a large amount of solid-solution Ni atoms. These findings can accelerate the development of additively manufactured titanium alloys. 展开更多
关键词 Ni addition microstructure refinement laser aided additive manufacturing titanium alloys strengthening mechanism
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Microstructure and property of laser additive manufactured alloy Ti-6Al-2V-1.5Mo-0.5Zr-0.3Si after aged at different temperatures
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作者 Guo-Chao Li Xu Cheng Hua-Ming Wang 《Rare Metals》 SCIE EI CAS CSCD 2024年第5期2275-2281,共7页
The solid solution and aging treatment for conventional manufacturing processes might not be suitable for laser additive manufactured titanium alloys due to the different lamellar microstructures.In this study,the inf... The solid solution and aging treatment for conventional manufacturing processes might not be suitable for laser additive manufactured titanium alloys due to the different lamellar microstructures.In this study,the influence of aging temperatures(600,700 and 800°C)on microstructure and mechanical properties of titanium alloy Ti-6Al-2V-1.5Mo-0.5Zr-0.3Si was investigated.The results indicate that after solid solution treatment at 970°C followed by water quenching,the alloy mainly consists of coarsening lamellar a phase in martensite α' matrix.Aging at 600°C will not change the size of primary lamellar α phase but lead to huge amount of secondary a phases(α_(s))generating with very fine microstructure.By increasing the aging temperature,the number of α_(s) decreases but with coarsened microstructures.When aged at 800°C,the width of the asphase reaches 350 nm,almost 7 times wider than that aged at 600°C.The changing size of α_(s) obviously influences the property of the alloy.The fine α_(s) leads to high strength and microhardness but low plasticity,and specimen aged at 700°C with suitable assize has the best comprehensive properties. 展开更多
关键词 α+βtitanium alloy laser additive manufacturing Solid solution and aging treatment Microstructure Room temperature tensile property
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Microstructure and Mechanical Properties of TiC-Reinforced Al–Mg–Sc–Zr Composites Additively Manufactured by Laser Direct Energy Deposition 被引量:2
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作者 Rong Xu Ruidi Li +2 位作者 Tiechui Yuan Hongbin Zhu Ping Li 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2022年第3期411-424,共14页
In order to refine the microstructure and improve the performance of direct energy deposited(DED)additively manufactured Al–Mg–Sc–Zr alloy,TiC-modified Al–Mg–Sc–Zr composites were prepared by DED and the effect ... In order to refine the microstructure and improve the performance of direct energy deposited(DED)additively manufactured Al–Mg–Sc–Zr alloy,TiC-modified Al–Mg–Sc–Zr composites were prepared by DED and the effect of TiC content on the microstructure and performance was studied.In the absence of TiC particle,the microstructure of Al–Mg–Sc–Zr alloy prepared by DED consisted of fine grains with average size of 8.36μm,and well-dispersed nano-Al;(Sc,Zr)particles inside the grains and Mg;Si phase along the grain boundaries.With the addition of 1 wt%TiC,the microstructure of TiC/Al–Mg–Sc–Zr prepared by DED became finer apparently compared with that without TiC;while the further increase of TiC content to 3 wt%,the microstructure of TiC/Al–Mg–Sc–Zr prepared by DED became coarser with appearance of a new kind of needle-like(Ti,Zr);Si;phase.Also,the addition of TiC decreased the porosity of Al–Mg–Sc–Zr prepared by DED.Simultaneously,after the addition of TiC,the tensile strength increased from 283.25 MPa to 344.98–361.51 MPa,and the elongation increased from 3.61%to 9.58–14.10%.The potential mechanism of the microstructure evolution and strength improvement was discussed.This research will provide new insights into the available metal matrix composites by laser additive manufacturing(LAM). 展开更多
关键词 laser additive manufacturing Aluminum matrix composites Mechanical property MICROSTRUCTURE
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