Research On Internal Friction Of Al-Zr Alloy

Aluminium and its alloy are widely used in various fields and have a series ofadvantages which are better than other alloys. Adding Zr elements to the aluminumalloy can improve the organization of the aluminium alloy and get better mechanicalproperties.The reports of Zr have been studying, Because the internal friction peaks ofthe Al-Zr alloy are more sophisticated, this thesis is trying to analyse and research thepeak of Al-Zr alloy internal friction in the high temperature condition again in order toexplore the influence of Zr element to alloy.By using internal friction inverted torsion pendulum,with the temperature reducing,drawed the internal friction curve of different temperature annealing Al-0.03wt%Zralloy filamentous samples which have been annealing and stretch treatment beforedrawing and drawed the internal friction curve of Al-0.04wt%Zr and Al-0.2wt%Zralloy filamentous samples in different annealing temperature and different holding time.Through the analysis of the curve of internal friction and the measurement of activationenergy, get situation of the changes of the internal friction peak with different heattreatment and deformation. By the metallographic photos of samples, auxiliary show ofthe influence of Zr element to the internal friction peak of Al-Zr alloy, to explore theinfluence of Zr element to alloy.Research found that the experimental process appeared in four internal frictionpeak， Respectively are grain boundary peak（P₁peak） due to grain boundary viscousand sliding, bamboo boundaries peak（P₂peak） due to second phase particles whichformed around the grain boundary after Zr elements and impurities was to be joined,High temperature peak（P3peak） due to dislocation substructure around the grainboundaries,and middle temperature peak （P4peak） due to the exercise of the scatteredparticles Al₃Zr around the grain boundaries.By the result of the study, the Al-0.03wt%Zr and Al-0.04wt%Zr samples contain Zr quantity is small,is not enough to curb alloy recrystallization behavior. scatteredparticles Al₃Zr can improve alloy recrystallization temperature and put the alloystabilizes.Zr element and trace elements have some obstacles role for disappearing ofdislocation in the course of room temperature manufacture,so the Al-0.2%Zrspecimens which have a high content of Zr arrive at the slubby temperature（823K and873K） or experience annealing after deformation or stretching deformation will have ahigher high-temperatuie background.