Diffusion welding was used to join SiCw/6061AI composites. The effects of welding pammeters on strength Of welded joint were investigated. JOint Of high quality for SiCw/6061Al composites can be obtained with aPPropri...Diffusion welding was used to join SiCw/6061AI composites. The effects of welding pammeters on strength Of welded joint were investigated. JOint Of high quality for SiCw/6061Al composites can be obtained with aPPropriate diffesion welding parameters.展开更多
The weldability of SiCw/6061Al -was investigated. From the results of experiments, it is found that the strength of joint is mainly influenced by welding temperature, and high strength of joint is obtained under meldi...The weldability of SiCw/6061Al -was investigated. From the results of experiments, it is found that the strength of joint is mainly influenced by welding temperature, and high strength of joint is obtained under melding temperature between liquidus and solidus of matrix alloy. Diffusion welding of SiCw/6061Al was successfully realized with appropriate ivelding parameters.展开更多
The effect of the low temperature treatment at -78 ℃ and -196 ℃ on the microstructure and properties of 18%SiC w/6061(volume fraction) Al alloy composites of as squeeze casting were studied. The results show that, a...The effect of the low temperature treatment at -78 ℃ and -196 ℃ on the microstructure and properties of 18%SiC w/6061(volume fraction) Al alloy composites of as squeeze casting were studied. The results show that, after the low temperature treatment, the dislocation density in matrix increases, and the residual stress of the matrix decreases, as well as the tensile yield strength of the composites improves. The high residual stress exists in the matrix of the composites of as original squeeze casting. The mismatch degree between the matrix and SiC w phases increases during the low temperature treatment. The matrix undergoes the tensile plastic deformation during the cooling procedure. On the contrary, the matrix encountered an elastic unloading procedure during the heating up process from low temperature to room temperature. The increase of dislocation density and the decrease of residual stress in the matrix are the main reason of the improvement for tensile yield strength of the composites.展开更多
Aluminum 6061 matrix composite reinforced by 35 wt% B4 C particle was fabricated by power metallurgy method. Then, the as-deformed composite was tested by quasi-static（0.001 s-1） and dynamic（760-1150 s-1） compress...Aluminum 6061 matrix composite reinforced by 35 wt% B4 C particle was fabricated by power metallurgy method. Then, the as-deformed composite was tested by quasi-static（0.001 s-1） and dynamic（760-1150 s-1） compression experiments. The Johnson-Cook plasticity model was employed to model the flow behavior. The damage mechanism of composite was analyzed through the microstructure observations. The results showed that the B4 C particles exhibited uniform distribution and no deleterious reaction product Al4C3 was found in the composite. Al6061/B4 C composite showed high yield strength, moderate strain rate sensitivity and strain hardening under the dynamic loading, and a constitutive model under dynamic compression was established based on Johnson-Cook model, and accorded well with experimental results. The microstructure damage was dominated by particle fracture and interface debonding, and the dislocation was observed in the composite at a higher strain rate.展开更多
文摘Diffusion welding was used to join SiCw/6061AI composites. The effects of welding pammeters on strength Of welded joint were investigated. JOint Of high quality for SiCw/6061Al composites can be obtained with aPPropriate diffesion welding parameters.
基金Funded by The National Nature Science Foundation (No. 59781004).
文摘The weldability of SiCw/6061Al -was investigated. From the results of experiments, it is found that the strength of joint is mainly influenced by welding temperature, and high strength of joint is obtained under melding temperature between liquidus and solidus of matrix alloy. Diffusion welding of SiCw/6061Al was successfully realized with appropriate ivelding parameters.
文摘The effect of the low temperature treatment at -78 ℃ and -196 ℃ on the microstructure and properties of 18%SiC w/6061(volume fraction) Al alloy composites of as squeeze casting were studied. The results show that, after the low temperature treatment, the dislocation density in matrix increases, and the residual stress of the matrix decreases, as well as the tensile yield strength of the composites improves. The high residual stress exists in the matrix of the composites of as original squeeze casting. The mismatch degree between the matrix and SiC w phases increases during the low temperature treatment. The matrix undergoes the tensile plastic deformation during the cooling procedure. On the contrary, the matrix encountered an elastic unloading procedure during the heating up process from low temperature to room temperature. The increase of dislocation density and the decrease of residual stress in the matrix are the main reason of the improvement for tensile yield strength of the composites.
基金financially supported by the Key Science and Technology Program of Shanxi Province,China(No.20130321024)the Graduate Innovation Project of Shanxi Province,China(No.B2014005)
文摘Aluminum 6061 matrix composite reinforced by 35 wt% B4 C particle was fabricated by power metallurgy method. Then, the as-deformed composite was tested by quasi-static（0.001 s-1） and dynamic（760-1150 s-1） compression experiments. The Johnson-Cook plasticity model was employed to model the flow behavior. The damage mechanism of composite was analyzed through the microstructure observations. The results showed that the B4 C particles exhibited uniform distribution and no deleterious reaction product Al4C3 was found in the composite. Al6061/B4 C composite showed high yield strength, moderate strain rate sensitivity and strain hardening under the dynamic loading, and a constitutive model under dynamic compression was established based on Johnson-Cook model, and accorded well with experimental results. The microstructure damage was dominated by particle fracture and interface debonding, and the dislocation was observed in the composite at a higher strain rate.
