Understanding the corrosion behavior of high entropy alloys(HEAs)after intermediate temperature fatigue is critical to prevent their catastrophic failures from the reduction of corrosion resistance.Here,we investigate...Understanding the corrosion behavior of high entropy alloys(HEAs)after intermediate temperature fatigue is critical to prevent their catastrophic failures from the reduction of corrosion resistance.Here,we investigated the corrosion behavior of CrMnFeCoNi HEA after 500℃ fatigue test with strain amplitudes of 0.2%and 0.5%.The intermediate temperature fatigue induced two types of precipitates,which were determined as Cr-richσphase and NiMn-rich L10 phase.Higher strain amplitude not only promoted precipitates generations but also spread the nucleation sites from intergranular to both intergranular and intragranular.Furthermore,we found that the deterioration in corrosion resistance of the alloy was derived from the increase of precipitates,which destroyed the stability of the passive film.The above results revealed that intermediate temperature fatigue impaired the stabilization of the solid solution state and subsequent corrosion resistance of CrMnFeCoNi HEA,where the higher strain amplitude led to more precipitates and more severe corrosion.展开更多
Microstructural and mechanical behavior of heat treatable Al-4.6Cu binary alloy reinforced with graphene nanoplates(GNPs) in different heat treatment status were investigated in this paper.The addition of GNPs signifi...Microstructural and mechanical behavior of heat treatable Al-4.6Cu binary alloy reinforced with graphene nanoplates(GNPs) in different heat treatment status were investigated in this paper.The addition of GNPs significantly enhanced the yield strength and tensile strength of Al-Cu alloy regardless of the heattreatment conditions.It was also found that GNPs accelerated the formation of precipitates,leading to a greatly shortened aging time for GNPs/Al-4.6Cu composite to reach the peak hardness.However,aging treatment enhanced the strength of GNPs/Al-Cu composite very little,which could be explained by the interaction between GNPs,precipitates and dislocations.This work inspires us that the heat treatment process of aluminum alloy matrix composites should be designed independently with the matrix in quest of an optimum performance.展开更多
基金the National Natural Science Foundation of China(Nos.52201072,12204143 and 52101013)the Natural Science Foundation of Hebei Province(No.E2020202009)+3 种基金the Technology Project of Hebei Education Department(No.QN2020150)the China Postdoctoral Science Foundation(No.2020M680843)the Central Funds Guiding the Local Science and Technology Development of Hebei Province(No.226Z1001G)the Central Funds Guiding the Local Science and Technology Development of Hebei Province(No.226Z1012G).
文摘Understanding the corrosion behavior of high entropy alloys(HEAs)after intermediate temperature fatigue is critical to prevent their catastrophic failures from the reduction of corrosion resistance.Here,we investigated the corrosion behavior of CrMnFeCoNi HEA after 500℃ fatigue test with strain amplitudes of 0.2%and 0.5%.The intermediate temperature fatigue induced two types of precipitates,which were determined as Cr-richσphase and NiMn-rich L10 phase.Higher strain amplitude not only promoted precipitates generations but also spread the nucleation sites from intergranular to both intergranular and intragranular.Furthermore,we found that the deterioration in corrosion resistance of the alloy was derived from the increase of precipitates,which destroyed the stability of the passive film.The above results revealed that intermediate temperature fatigue impaired the stabilization of the solid solution state and subsequent corrosion resistance of CrMnFeCoNi HEA,where the higher strain amplitude led to more precipitates and more severe corrosion.
基金financially support by the Equipment Advance Research Fund (Grant No. 61409220102)the Chinese National Science Fund for Distinguished Young Scholars (Grant No. 52025015)+2 种基金the Chinese National Natural Science Foundation (Grant No. 51771130, 52071230)the Tianjin youth talent support program, the Tianjin Natural Science Funds for Distinguished Young Scholars (Grant No. 17JCJQJC44300)the Tianjin Science and Technology Support Project (Grant No. 17ZXCLGX00060)。
文摘Microstructural and mechanical behavior of heat treatable Al-4.6Cu binary alloy reinforced with graphene nanoplates(GNPs) in different heat treatment status were investigated in this paper.The addition of GNPs significantly enhanced the yield strength and tensile strength of Al-Cu alloy regardless of the heattreatment conditions.It was also found that GNPs accelerated the formation of precipitates,leading to a greatly shortened aging time for GNPs/Al-4.6Cu composite to reach the peak hardness.However,aging treatment enhanced the strength of GNPs/Al-Cu composite very little,which could be explained by the interaction between GNPs,precipitates and dislocations.This work inspires us that the heat treatment process of aluminum alloy matrix composites should be designed independently with the matrix in quest of an optimum performance.
