Because of the challenge of compounding lightweight,high-strength Ti/Al alloys due to their considerable disparity in properties,Al 6063 as intermediate layer was proposed to fabricate TC4/Al 6063/Al 7075 three-layer ...Because of the challenge of compounding lightweight,high-strength Ti/Al alloys due to their considerable disparity in properties,Al 6063 as intermediate layer was proposed to fabricate TC4/Al 6063/Al 7075 three-layer composite plate by explosive welding.The microscopic properties of each bonding interface were elucidated through field emission scanning electron microscope and electron backscattered diffraction(EBSD).A methodology combining finite element method-smoothed particle hydrodynamics(FEM-SPH)and molecular dynamics(MD)was proposed for the analysis of the forming and evolution characteristics of explosive welding interfaces at multi-scale.The results demonstrate that the bonding interface morphologies of TC4/Al 6063 and Al 6063/Al 7075 exhibit a flat and wavy configuration,without discernible defects or cracks.The phenomenon of grain refinement is observed in the vicinity of the two bonding interfaces.Furthermore,the degree of plastic deformation of TC4 and Al 7075 is more pronounced than that of Al 6063 in the intermediate layer.The interface morphology characteristics obtained by FEM-SPH simulation exhibit a high degree of similarity to the experimental results.MD simulations reveal that the diffusion of interfacial elements predominantly occurs during the unloading phase,and the simulated thickness of interfacial diffusion aligns well with experimental outcomes.The introduction of intermediate layer in the explosive welding process can effectively produce high-quality titanium/aluminum alloy composite plates.Furthermore,this approach offers a multi-scale simulation strategy for the study of explosive welding bonding interfaces.展开更多
通过向Ag Cu共晶钎料中添加nano-Al2O3增强相(2%,质量分数)并采用高能球磨的方法获得了Ag Cu+nano-Al2O3复合钎料(Ag Cu C钎料)。采用Ag Cu C钎料实现了TC4合金与Al2O3陶瓷的高质量钎焊连接,确定了TC4/Ag Cu C/Al2O3钎焊接头的典型界面...通过向Ag Cu共晶钎料中添加nano-Al2O3增强相(2%,质量分数)并采用高能球磨的方法获得了Ag Cu+nano-Al2O3复合钎料(Ag Cu C钎料)。采用Ag Cu C钎料实现了TC4合金与Al2O3陶瓷的高质量钎焊连接,确定了TC4/Ag Cu C/Al2O3钎焊接头的典型界面组织结构为:TC4/α-Ti+Ti2Cu扩散层/Ti3Cu4层/Ag(s,s)+Ti3Cu4+Ti Cu/Ti3Cu4层/Ti3(Cu,Al)3O层/Al2O3。Nano-Al2O3的添加抑制了钎缝中连续的Ti-Cu化合物层的生长,同时在钎缝中形成了颗粒状Ti-Cu化合物相增强的Ag基复合材料,改善了钎焊接头的界面组织。随着钎焊温度的升高,各反应层厚度逐渐增加,颗粒状Ti-Cu化合物不断长大,Ag基复合材料组织逐渐细小。当钎焊温度T=920℃,保温时间t=10 min时接头抗剪强度达到最大为67.8 MPa,典型断口分析表明:压剪过程中,裂纹起源于钎角处并沿钎缝扩展后转入Al2O3陶瓷,最终在Al2O3陶瓷母材侧发生断裂。展开更多
The successful joining of carbon fiber-reinforced aluminum matrix(C_(f)/Al)composites and TC4 alloy can produce composite structure and meet the demands of lightweight in aerospace field.Up to now,few experimental res...The successful joining of carbon fiber-reinforced aluminum matrix(C_(f)/Al)composites and TC4 alloy can produce composite structure and meet the demands of lightweight in aerospace field.Up to now,few experimental researches have been reported on the joining of C_(f)/Al composites and TC4 alloy.In this study,the AgCu foils and Ni-Al-Zr compact were designed for the self-propagating high-temperature synthesis joining of these two materials.C_(f)/Al composites were joined with a reactive Ti plated on its joining surface.The typical microstructure of TC4/(AgCu/Ni-Al-Zr/AgCu)/Ti/C_(f)/Al joint was analyzed,and the effects of joining condition on microstructural evolution of the SHS joint were investigated.A thin reaction layer of Ni-Al-Ti intermetallic compounds was formed adjacent to the TC4 alloy.As a result,AgCu foils could reduce the effect of reaction heat on the substrates and improve the joint shear strength.When the thickness of AgCu foils reaches 150 lm,the Ni-Al-Zr interlayer mainly acts as auxiliary heat source.High joining pressure caused the active elements to diffuse into C_(f)/Al composites and weakened the shear strength of the joint.Finally,the joint shear strength could reach 36.4 MPa when the AgCu foils were 50 lm and the joining pressure was 2 MPa.展开更多
The C_(f)/Al composites were joined to the TC4 alloy via the laser-induced combustion joining method.The exothermic reaction of the interlayer provided the required energy for the joining process.By combining the theo...The C_(f)/Al composites were joined to the TC4 alloy via the laser-induced combustion joining method.The exothermic reaction of the interlayer provided the required energy for the joining process.By combining the theoretical calculation and experiment,the chemical composition of the Ni−Al−Zr interlayer was designed.The microstructure and mechanical properties of the joint were investigated.The results show that the addition of Zr slightly weakened the combustion reaction of exothermic interlayer but played a key role in the successful joining.Ni−Al−Zr interlayer reacted with substrates,forming a TiAl_(3)layer adjacent to TC4 alloy and NiAl_(3),Ni_(2)Al_(3)layers adjacent to the C_(f)/Al composites.Zr content dominated the microstructure and shear strength of the joint.When the Zr content was 5 wt.%under the joining pressure of 2 MPa,the joint had a maximum shear strength of 19.8 MPa.展开更多
基金Opening Foundation of Key Laboratory of Explosive Energy Utilization and Control,Anhui Province(BP20240104)Graduate Innovation Program of China University of Mining and Technology(2024WLJCRCZL049)Postgraduate Research&Practice Innovation Program of Jiangsu Province(KYCX24_2701)。
文摘Because of the challenge of compounding lightweight,high-strength Ti/Al alloys due to their considerable disparity in properties,Al 6063 as intermediate layer was proposed to fabricate TC4/Al 6063/Al 7075 three-layer composite plate by explosive welding.The microscopic properties of each bonding interface were elucidated through field emission scanning electron microscope and electron backscattered diffraction(EBSD).A methodology combining finite element method-smoothed particle hydrodynamics(FEM-SPH)and molecular dynamics(MD)was proposed for the analysis of the forming and evolution characteristics of explosive welding interfaces at multi-scale.The results demonstrate that the bonding interface morphologies of TC4/Al 6063 and Al 6063/Al 7075 exhibit a flat and wavy configuration,without discernible defects or cracks.The phenomenon of grain refinement is observed in the vicinity of the two bonding interfaces.Furthermore,the degree of plastic deformation of TC4 and Al 7075 is more pronounced than that of Al 6063 in the intermediate layer.The interface morphology characteristics obtained by FEM-SPH simulation exhibit a high degree of similarity to the experimental results.MD simulations reveal that the diffusion of interfacial elements predominantly occurs during the unloading phase,and the simulated thickness of interfacial diffusion aligns well with experimental outcomes.The introduction of intermediate layer in the explosive welding process can effectively produce high-quality titanium/aluminum alloy composite plates.Furthermore,this approach offers a multi-scale simulation strategy for the study of explosive welding bonding interfaces.
文摘通过向Ag Cu共晶钎料中添加nano-Al2O3增强相(2%,质量分数)并采用高能球磨的方法获得了Ag Cu+nano-Al2O3复合钎料(Ag Cu C钎料)。采用Ag Cu C钎料实现了TC4合金与Al2O3陶瓷的高质量钎焊连接,确定了TC4/Ag Cu C/Al2O3钎焊接头的典型界面组织结构为:TC4/α-Ti+Ti2Cu扩散层/Ti3Cu4层/Ag(s,s)+Ti3Cu4+Ti Cu/Ti3Cu4层/Ti3(Cu,Al)3O层/Al2O3。Nano-Al2O3的添加抑制了钎缝中连续的Ti-Cu化合物层的生长,同时在钎缝中形成了颗粒状Ti-Cu化合物相增强的Ag基复合材料,改善了钎焊接头的界面组织。随着钎焊温度的升高,各反应层厚度逐渐增加,颗粒状Ti-Cu化合物不断长大,Ag基复合材料组织逐渐细小。当钎焊温度T=920℃,保温时间t=10 min时接头抗剪强度达到最大为67.8 MPa,典型断口分析表明:压剪过程中,裂纹起源于钎角处并沿钎缝扩展后转入Al2O3陶瓷,最终在Al2O3陶瓷母材侧发生断裂。
基金the National Natural Science Foundation of China(Nos.51975149 and 51905055)the Central Universities Project(No.2019CDXYCL0031)。
文摘The successful joining of carbon fiber-reinforced aluminum matrix(C_(f)/Al)composites and TC4 alloy can produce composite structure and meet the demands of lightweight in aerospace field.Up to now,few experimental researches have been reported on the joining of C_(f)/Al composites and TC4 alloy.In this study,the AgCu foils and Ni-Al-Zr compact were designed for the self-propagating high-temperature synthesis joining of these two materials.C_(f)/Al composites were joined with a reactive Ti plated on its joining surface.The typical microstructure of TC4/(AgCu/Ni-Al-Zr/AgCu)/Ti/C_(f)/Al joint was analyzed,and the effects of joining condition on microstructural evolution of the SHS joint were investigated.A thin reaction layer of Ni-Al-Ti intermetallic compounds was formed adjacent to the TC4 alloy.As a result,AgCu foils could reduce the effect of reaction heat on the substrates and improve the joint shear strength.When the thickness of AgCu foils reaches 150 lm,the Ni-Al-Zr interlayer mainly acts as auxiliary heat source.High joining pressure caused the active elements to diffuse into C_(f)/Al composites and weakened the shear strength of the joint.Finally,the joint shear strength could reach 36.4 MPa when the AgCu foils were 50 lm and the joining pressure was 2 MPa.
基金the financial supports from the National Natural Science Foundation of China(Nos.51975149,51905055)the Natural Science Foundation of Chongqing,China(No.cstc2020jcyj-msxmX0115)the Fundamental Research Funds for the Central Universities Project,China(No.2020CDJ-LHZZ 086).
文摘The C_(f)/Al composites were joined to the TC4 alloy via the laser-induced combustion joining method.The exothermic reaction of the interlayer provided the required energy for the joining process.By combining the theoretical calculation and experiment,the chemical composition of the Ni−Al−Zr interlayer was designed.The microstructure and mechanical properties of the joint were investigated.The results show that the addition of Zr slightly weakened the combustion reaction of exothermic interlayer but played a key role in the successful joining.Ni−Al−Zr interlayer reacted with substrates,forming a TiAl_(3)layer adjacent to TC4 alloy and NiAl_(3),Ni_(2)Al_(3)layers adjacent to the C_(f)/Al composites.Zr content dominated the microstructure and shear strength of the joint.When the Zr content was 5 wt.%under the joining pressure of 2 MPa,the joint had a maximum shear strength of 19.8 MPa.
