Qa110-5-5 Aluminum Bronze Alloy Microstructure And Properties Research

The effects of different heat treatments on the microstructure and properties of forged QAl10-5-5aluminum bronze alloy were studied by hardness test, tens-ile properties test at room temperature and at elevated temperatures,optical micro-scopy, X-ray diffraction and electronic microscopy analysis.Meanwhile the micr-ostructure and properties of forged alloy at high temperature of different heat tre-atments were studied and analysis,and the best heat treatment process was obtain-ed to meet the practice manufacturing production.The results show that:1) The optimal solution regime of forged QAl10-5-5aluminum bronze alloy is950℃/2h.On this condition,the mechanical properties can be obtained: hardness, tensile strength,yield strength and elongation of the alloy reaches256HB,801MPa,490MPa and3.0%,respectively.The higher hardness and strength of the forged alloy was obtained after solution and quenching as the results of β�'β’ marten-site transformation and solution strengthening.2) The mechanical properties of the solution and quenching alloy can be further improved after aging treatment. The higher hardness and strength of the alloy can be obtained after they were aged at400℃for2hours and the hardness, tensile strength, yield strength reaches264HB,854MPa,638MPa respectively,but the elongation only reaches1.1%.The better combination of the strength and toug-hness of the alloy can be obtained after they were aged at650℃for2hours.On this condition,the hardness,tensile strength,yield strength and elongation of the al-loy reaches210HB,764MPa,484MPa and21.5%,respectively.The fine granular κ phase precipitated from the supersaturated solid solution α phase and β’martens-ite formed precipitation strength in the process of aging treatment.3) The mechanical properties of forged QAl10-5-5aluminum bronze can be improved after stabilization annealing treatment. After annealing treatment at650℃for2hours, the hardness, tensile strength, yield strength and elongation of the alloy reaches212HB,769MPa,492Mpa and18.3%, respectively, compared with the forged alloy, the hardness, tensile strength, yield strength and elongation increase8.16%,6.22%,12.33%and14.13%, respectively. After stabilization annealing treatment, the hard and brittle of small (α+γ2) eutectoid was uniformly distributed among the soft a phase, the higher hardness and strength of the fine granular κ phase dispersed between the microstructure of a phase and (α+γ2) eutectoid.4) Both the tensile strength and yield strength of the forged alloy decreased with the alloy was tensiled between100℃～450℃after stabilization annealing treatment at650℃for2hours.However,the elongation decreased first and increased after300℃.The alloy remain holds the higher tensile strength、yield strength and elongation when was tensiled at450℃after stabilization annealing treatment, reaches456MPa,335MPa and15.8%,respectively. it can meet the mechanical properties requirements of the retaining ring at the high temperature.