The insufficient damping capabilities of aluminum alloy under low temperatures(<120℃)were addressed by developing high-damping laminated composites of NiTip/5052Al.This is achieved through the incorporation of var...The insufficient damping capabilities of aluminum alloy under low temperatures(<120℃)were addressed by developing high-damping laminated composites of NiTip/5052Al.This is achieved through the incorporation of varied pre-aging states of NiTi particles into the 5052Al matrix using a rolling composite technique.The aim is to enhance the application scope of aluminum alloy for vibration and noise reduction.The results demonstrated a distinct and integrated interface between the particle layer and the 5052Al alloy,with numerous interparticle interfaces within the particle layer.Increasing the aging temperature of the NiTi particles from 450 to 550℃ shifted the phase transition peaks of the composites to lower temperatures.The damping capacity of the laminated NiTip/5052Al composites notably surpasses that of the 5052Al alloy.At 28 and 66℃,the phase transformation damping peaks of the pre-aged NiTi particle layer reinforced 5052Al matrix composites are 1.93 and 2 times those of the 5052Al alloy at the corresponding temperatures,respectively.The collaborative impact of interparticle interface damping mechanism and the phase transformation damping mechanism of NiTi-reinforced particles significantly amplify the low-temperature damping performance of the laminated NiTip/5052Al composites.展开更多
Constrained groove pressing(CGP)is a severe plastic deformation(SPD)technique used as a strengthening method for sheet metal.In the current work,an optimal/cost-saving design for CGP dies was attained using the stress...Constrained groove pressing(CGP)is a severe plastic deformation(SPD)technique used as a strengthening method for sheet metal.In the current work,an optimal/cost-saving design for CGP dies was attained using the stress analysis tool in SolidWorks Simulation Xpress wizard.This study examined low-cost and widely industrially applied aluminium materials,i.e.,pure 1050 Al and 5052 Al alloy.Each material was subjected to three passes of the CGP process using a 150 tons capacity press.For both materials,inter-pass annealing treatment was undertaken before the third pass.The effect of the number of CGP passes on the microstructure and tensile properties was studied after each pass.For CGPed pure 1050 Al with respect to the as-received material,the ultimate tensile strength(UTS),yield strength(YS)and YS/UTS ratio increased with an increasing number of CGP passes until the second pass,while elongation decreased with the number of passes.For CGPed 5052 Al alloy,the UTS and YS increased after the first pass and then decreased after the second pass.Variations in the elongation and YS/UTS ratio of 5052 Al alloy after the CGP process were insignificant.After inter-pass annealing and applying the third CGP pass,the strength of pure 1050 Al decreased,and that of 5052 Al alloy increased,which was attributed to the influence of composition on their structures.The strength-ductility balance decreased with an increasing number of CGP passes in both materials.展开更多
Lap Joining of 5052 aluminum alloy(Al5052)to Ti6Al4V titanium alloy(Ti6Al4V)was conducted by gas tungsten arc welding(GTAW)process with AlSi5 filler wire.Microstructure examination revealed that non-uniform persistent...Lap Joining of 5052 aluminum alloy(Al5052)to Ti6Al4V titanium alloy(Ti6Al4V)was conducted by gas tungsten arc welding(GTAW)process with AlSi5 filler wire.Microstructure examination revealed that non-uniform persistent reaction layer developed in Al5052/Ti6Al4V interfacial area,and the intermetallic compounds(IMCs)layer of Ti(Al,Si)3 phase formed with the partial substitution of aluminum by silicon.The thickness of IMCs layer varied from less than 1μm to more than 5μm in accordance with rise in welding current.Aluminum,silicon and titanium elements in the IMCs layer and weld zone were identified by electron probe microanalysis(EPMA).The results demonstrated that sound Al5052/Ti6Al4V joints can be achieved in the range of 50 A–60 A welding current.The maximum tensile shear strength of 293 N/mm was attained at the optimized welding parameter and the joint fractured in the weld zone.Additionally,the micro-Vickers hardness at Al5052/Ti6Al4V interface was relatively higher in comparison with that of the weld seam and Ti6Al4V base metal as a consequence of IMCs formation.展开更多
基金National Natural Science Foundation of China (No. 52061011)Guangxi Natural Science Foundation,China (No. 2022GXNSFAA035574)Innovation Project of Guangxi Graduate Education,China (No. YCSW2023361)。
文摘The insufficient damping capabilities of aluminum alloy under low temperatures(<120℃)were addressed by developing high-damping laminated composites of NiTip/5052Al.This is achieved through the incorporation of varied pre-aging states of NiTi particles into the 5052Al matrix using a rolling composite technique.The aim is to enhance the application scope of aluminum alloy for vibration and noise reduction.The results demonstrated a distinct and integrated interface between the particle layer and the 5052Al alloy,with numerous interparticle interfaces within the particle layer.Increasing the aging temperature of the NiTi particles from 450 to 550℃ shifted the phase transition peaks of the composites to lower temperatures.The damping capacity of the laminated NiTip/5052Al composites notably surpasses that of the 5052Al alloy.At 28 and 66℃,the phase transformation damping peaks of the pre-aged NiTi particle layer reinforced 5052Al matrix composites are 1.93 and 2 times those of the 5052Al alloy at the corresponding temperatures,respectively.The collaborative impact of interparticle interface damping mechanism and the phase transformation damping mechanism of NiTi-reinforced particles significantly amplify the low-temperature damping performance of the laminated NiTip/5052Al composites.
文摘Constrained groove pressing(CGP)is a severe plastic deformation(SPD)technique used as a strengthening method for sheet metal.In the current work,an optimal/cost-saving design for CGP dies was attained using the stress analysis tool in SolidWorks Simulation Xpress wizard.This study examined low-cost and widely industrially applied aluminium materials,i.e.,pure 1050 Al and 5052 Al alloy.Each material was subjected to three passes of the CGP process using a 150 tons capacity press.For both materials,inter-pass annealing treatment was undertaken before the third pass.The effect of the number of CGP passes on the microstructure and tensile properties was studied after each pass.For CGPed pure 1050 Al with respect to the as-received material,the ultimate tensile strength(UTS),yield strength(YS)and YS/UTS ratio increased with an increasing number of CGP passes until the second pass,while elongation decreased with the number of passes.For CGPed 5052 Al alloy,the UTS and YS increased after the first pass and then decreased after the second pass.Variations in the elongation and YS/UTS ratio of 5052 Al alloy after the CGP process were insignificant.After inter-pass annealing and applying the third CGP pass,the strength of pure 1050 Al decreased,and that of 5052 Al alloy increased,which was attributed to the influence of composition on their structures.The strength-ductility balance decreased with an increasing number of CGP passes in both materials.
基金supported by the National Natural Science Foundation of China(51674060)the Fundamental Research Funds for the Central Universities(DUT18LAB01)the Collaborative Innovation Center of Major Machine Manufacturing in Liaoning
文摘Lap Joining of 5052 aluminum alloy(Al5052)to Ti6Al4V titanium alloy(Ti6Al4V)was conducted by gas tungsten arc welding(GTAW)process with AlSi5 filler wire.Microstructure examination revealed that non-uniform persistent reaction layer developed in Al5052/Ti6Al4V interfacial area,and the intermetallic compounds(IMCs)layer of Ti(Al,Si)3 phase formed with the partial substitution of aluminum by silicon.The thickness of IMCs layer varied from less than 1μm to more than 5μm in accordance with rise in welding current.Aluminum,silicon and titanium elements in the IMCs layer and weld zone were identified by electron probe microanalysis(EPMA).The results demonstrated that sound Al5052/Ti6Al4V joints can be achieved in the range of 50 A–60 A welding current.The maximum tensile shear strength of 293 N/mm was attained at the optimized welding parameter and the joint fractured in the weld zone.Additionally,the micro-Vickers hardness at Al5052/Ti6Al4V interface was relatively higher in comparison with that of the weld seam and Ti6Al4V base metal as a consequence of IMCs formation.
