Laser oscillating welding of 2205 duplex stainless steel was performed using Ni interlayer as filler material.The influence of stirring effect caused by laser oscillating and Ni addition in the behavior of molten pool...Laser oscillating welding of 2205 duplex stainless steel was performed using Ni interlayer as filler material.The influence of stirring effect caused by laser oscillating and Ni addition in the behavior of molten pool and the microstructure evolution was investigated.The results shows that Ni addition decreased the ratio of chromium equivalent and nickel equivalent in the molten pool and accelerated the austenitic transformation.The austenite/ferrite ratio was regulated,and the precipitation of nitrides was suppressed in the weld seam.The stirring effect caused by the oscillating beam facilitated the uniform distribution of Ni elements within the molten pool,promoting the formation of the homogeneous microstructures in the weld seam.With increasing the thickness of Ni interlayer,both the dimension and the peak temperature of molten pool decrease,further increasing the cooling rate and refining the grain size.When the thickness of Ni interlayer was 50μm,the austenite/ferrite ratio in the weld seam was close to 1:1,and the grain size reached the minimum value.The tensile strength and ductility of the welded joint using Ni interlayer with thickness were 774 MPa and 25%,respectively,significantly improving the mechanical properties of 2205 duplex stainless steel joint welded without Ni addition.展开更多
In the present study, impulse pressuring diffu- sion bonding technology （IPDB） was utilized between commercially pure titanium and 304 stainless steel （SS） using pure nickel （Ni） as interlayer metal. The interfa...In the present study, impulse pressuring diffu- sion bonding technology （IPDB） was utilized between commercially pure titanium and 304 stainless steel （SS） using pure nickel （Ni） as interlayer metal. The interfacial microstructures of the bonded joints were investigated by scanning electron microscopy （SEM） and energy dispersive spectroscope （EDS） analyses. It is found that with the aid of the Ni interlayer, the interdiffusion and reaction between Ti and SS can be effectively restricted and robust joints can be obtained. Intermetallic compounds （IMCs） including Ti2Ni, TiNi, and TiNi3 are detected at the Ti/Ni interface; however, only Ni-Fe solid solution is found at the Ni/SS interface. The maximum tensile strength of 358 MPa is obtained by IPDB for 90 s and the fracture takes place along the Ti2Ni and TiNi phase upon tensile loading. The existence of cleavage pattern on the fracture surface indi- cates the brittle nature of the joints.展开更多
Through the vacuum diffusion welding SiC_p/ZL101 aluminum with Ni interlayer,the effect of welding parameter and the thickness property of Ni on the welded joint wasinvestigated, and the optimal welding parameters wer...Through the vacuum diffusion welding SiC_p/ZL101 aluminum with Ni interlayer,the effect of welding parameter and the thickness property of Ni on the welded joint wasinvestigated, and the optimal welding parameters were put forward at the same time. Themicrostructure of joint was analyzed by means of optical-microscope, scanning electron microscope(SEM) in order to study the relationship between the macro-properties of joint and themicrostructure. The results show that diffusion welding with Ni interlayer can be used for weldingaluminum matrix composites SiC_p/ZL101 successfully. Under the welding parameters T=560℃, P=5 MPa,t=60 min, H=14μm, the bonding strength of welded joint can up to 121 MPa. Moreover, the thicknessof interlayer should match with the size of reinforced particles. If the thickness of interlayer istoo thin, it would have no effect on the welded joint beneficially. If the thickness of interlayeris too thick, it would cause the 'no-reinforcement zone' to appear.展开更多
Ti-6Al-4V and QAl 10-3-1.5 diffusion bonding has been carried out with Ni/Cu interlayers. The diffusionbonded joints are evaluated by scanning electron microscopy （SEM）, energy dispersive spectroscopy （EDS） and mi...Ti-6Al-4V and QAl 10-3-1.5 diffusion bonding has been carried out with Ni/Cu interlayers. The diffusionbonded joints are evaluated by scanning electron microscopy （SEM）, energy dispersive spectroscopy （EDS） and microhardness test. Intermetallic compounds at the interface zone are detected by X-ray diffraction （XRD）. Interracial microstructure of TiNi＋CuTi3＋α-Ti forms at the Ni/Ti-6Al-4V transition zone and Cu （ss. Ni） solid solution forms between Ni/Cu interlayers. The thickness of reaction layer （TiNi） increases with bonding time by a parabolic law： y^2=Koexp（-150000/RT）t, and K0=2.g×10^-7 m^2/s is figured out from the experiment data.展开更多
In this research,2205/Q235 B clad plates were prepared by a vacuum hot rolling composite process.The effects of adding Fe,Ni,and Nb interlayers on the bonding interface structures and the shear strengths of the clad s...In this research,2205/Q235 B clad plates were prepared by a vacuum hot rolling composite process.The effects of adding Fe,Ni,and Nb interlayers on the bonding interface structures and the shear strengths of the clad steel plates were studied.The results showed that 2205 duplex stainless steel and the three interlayers produced a large amount of plastic deformation and low-angle boundaries,and the main structures were the recrystallized and deformed grains.There were many recrystallized grains in the microstructure of the Q235 B low-carbon steel due to the low deformation in the rolling process.The Fe interlayer had better wettability with the two kinds of steel,but the lower strength led to the reduction of shear strength by about14 MPa compared with the original clad steel plate.The C element in the Q235 B low-carbon steel easily diffused into the Fe interlayer,and the clad steel plate attained a poor corrosion resistance because a large decarburization area was formed.The Nb interlayer reacted with the Mo element in the 2205 duplex stainless steel to form an Nb-Mo binary alloy,which generated long-banded ferrite.The decarburization area was also produced because the Nb reacted with the C element in the Q235 B to form hard and brittle NbCx.As a result,the shear strength was significantly reduced by about 282 MPa,and the corrosion resistance of the bonding surface was deteriorated.The Ni interlayer did not react with the alloy elements in both sides,and therefore effectively prevented element diffusion and improved the corrosion resistance of the bonding surface.Due to the low strength of the Ni interlayer and the increased number of bonding surfaces of the clad steel plates,the shear strength was reduced to some extent(about 40 MPa),but it still met the engineering application standards.展开更多
基金financially supported by the National Natural Science Foundation of China(51805084 and 52265062)Project National United Engineering Laboratory for Advanced Bearing Tribology(202207)Guangdong Basic and Applied Basic Research Foundation(2023B1515120086 and 2023A1515140124).
文摘Laser oscillating welding of 2205 duplex stainless steel was performed using Ni interlayer as filler material.The influence of stirring effect caused by laser oscillating and Ni addition in the behavior of molten pool and the microstructure evolution was investigated.The results shows that Ni addition decreased the ratio of chromium equivalent and nickel equivalent in the molten pool and accelerated the austenitic transformation.The austenite/ferrite ratio was regulated,and the precipitation of nitrides was suppressed in the weld seam.The stirring effect caused by the oscillating beam facilitated the uniform distribution of Ni elements within the molten pool,promoting the formation of the homogeneous microstructures in the weld seam.With increasing the thickness of Ni interlayer,both the dimension and the peak temperature of molten pool decrease,further increasing the cooling rate and refining the grain size.When the thickness of Ni interlayer was 50μm,the austenite/ferrite ratio in the weld seam was close to 1:1,and the grain size reached the minimum value.The tensile strength and ductility of the welded joint using Ni interlayer with thickness were 774 MPa and 25%,respectively,significantly improving the mechanical properties of 2205 duplex stainless steel joint welded without Ni addition.
基金financially supported by the National Natural Science Foundation of China(No.50675234)
文摘In the present study, impulse pressuring diffu- sion bonding technology （IPDB） was utilized between commercially pure titanium and 304 stainless steel （SS） using pure nickel （Ni） as interlayer metal. The interfacial microstructures of the bonded joints were investigated by scanning electron microscopy （SEM） and energy dispersive spectroscope （EDS） analyses. It is found that with the aid of the Ni interlayer, the interdiffusion and reaction between Ti and SS can be effectively restricted and robust joints can be obtained. Intermetallic compounds （IMCs） including Ti2Ni, TiNi, and TiNi3 are detected at the Ti/Ni interface; however, only Ni-Fe solid solution is found at the Ni/SS interface. The maximum tensile strength of 358 MPa is obtained by IPDB for 90 s and the fracture takes place along the Ti2Ni and TiNi phase upon tensile loading. The existence of cleavage pattern on the fracture surface indi- cates the brittle nature of the joints.
基金This work was supported by the National Natural Science Foundation of China (No.50171025).
文摘Through the vacuum diffusion welding SiC_p/ZL101 aluminum with Ni interlayer,the effect of welding parameter and the thickness property of Ni on the welded joint wasinvestigated, and the optimal welding parameters were put forward at the same time. Themicrostructure of joint was analyzed by means of optical-microscope, scanning electron microscope(SEM) in order to study the relationship between the macro-properties of joint and themicrostructure. The results show that diffusion welding with Ni interlayer can be used for weldingaluminum matrix composites SiC_p/ZL101 successfully. Under the welding parameters T=560℃, P=5 MPa,t=60 min, H=14μm, the bonding strength of welded joint can up to 121 MPa. Moreover, the thicknessof interlayer should match with the size of reinforced particles. If the thickness of interlayer istoo thin, it would have no effect on the welded joint beneficially. If the thickness of interlayeris too thick, it would cause the 'no-reinforcement zone' to appear.
基金The financial supports from the National Natural Science Foundation of China(NSFC)under Grant No.50375065the National Key Laboratory of Advanced Welding Production Technology are acknowledged.
文摘Ti-6Al-4V and QAl 10-3-1.5 diffusion bonding has been carried out with Ni/Cu interlayers. The diffusionbonded joints are evaluated by scanning electron microscopy （SEM）, energy dispersive spectroscopy （EDS） and microhardness test. Intermetallic compounds at the interface zone are detected by X-ray diffraction （XRD）. Interracial microstructure of TiNi＋CuTi3＋α-Ti forms at the Ni/Ti-6Al-4V transition zone and Cu （ss. Ni） solid solution forms between Ni/Cu interlayers. The thickness of reaction layer （TiNi） increases with bonding time by a parabolic law： y^2=Koexp（-150000/RT）t, and K0=2.g×10^-7 m^2/s is figured out from the experiment data.
基金financially supported by the Shandong Taishan Industry Leading Talents Project(SF1503302301)
文摘In this research,2205/Q235 B clad plates were prepared by a vacuum hot rolling composite process.The effects of adding Fe,Ni,and Nb interlayers on the bonding interface structures and the shear strengths of the clad steel plates were studied.The results showed that 2205 duplex stainless steel and the three interlayers produced a large amount of plastic deformation and low-angle boundaries,and the main structures were the recrystallized and deformed grains.There were many recrystallized grains in the microstructure of the Q235 B low-carbon steel due to the low deformation in the rolling process.The Fe interlayer had better wettability with the two kinds of steel,but the lower strength led to the reduction of shear strength by about14 MPa compared with the original clad steel plate.The C element in the Q235 B low-carbon steel easily diffused into the Fe interlayer,and the clad steel plate attained a poor corrosion resistance because a large decarburization area was formed.The Nb interlayer reacted with the Mo element in the 2205 duplex stainless steel to form an Nb-Mo binary alloy,which generated long-banded ferrite.The decarburization area was also produced because the Nb reacted with the C element in the Q235 B to form hard and brittle NbCx.As a result,the shear strength was significantly reduced by about 282 MPa,and the corrosion resistance of the bonding surface was deteriorated.The Ni interlayer did not react with the alloy elements in both sides,and therefore effectively prevented element diffusion and improved the corrosion resistance of the bonding surface.Due to the low strength of the Ni interlayer and the increased number of bonding surfaces of the clad steel plates,the shear strength was reduced to some extent(about 40 MPa),but it still met the engineering application standards.
