Research On Structure And Heat Treatment Performance Of Aluminum Alloy

A new type of Al-Cu alloy as the main research object was studied in this paper, the influence of the heat treatment process on the microstructure and properties of the material were researched. And its purpose is to improve the performance of structural material. A new method of metallic material phase transition measurement named Specific Volume Difference Method (SVDM) was be applied in this paper, and the validity of this new analysis method was be confirmed by the experimental measurements of different series of aluminum alloys. The systematic study of new materials were be analyzed by this new method, and the new method were be quantitative verified by thermal expansion measurements and X-ray diffraction. The results were based on SVDM, a new strengthening mechanism of aluminum alloys i.e., the phase transition stress strengthening was also proposed in this paper.The results indicated that, SVDM is an efficient and accurate method in the process of aluminum alloy heat treatment of phase transition test the validity of the quantitative analysis and research specific volume difference method, and SVDM were not only applied in 211Z aluminum alloy, but also can be applied in heat treatment during the phase transition of any other aluminum alloy.The analysis results of thermal expansion and XRD indicated that SVDM is a convenient method, and the results are accurate, reliable and small error. Results under different conditions of aging process indicate that with the change of aging time, the mechanical properties of material were also changed, the results are the same with SVDM, the effectiveness of SVDM can be also proved further.During the study of hardenability experiment of 211Z aluminum, the hardenability of materials were test by hardness testing, which will play an important role in the actual production. Based on the results of T phase electron diffraction, the structure of T phase were be researched by XRD further.Due to the change of phase transformation on the specific volume of material, it can be evolved that phase transition will occur residual stresses during the inside of material, the results were be confirmed by XRD. A new strengthening mechanism of the 6061 aluminum alloy under the statement of T6 were be proposed in this paper, a residual stresses which occur from phase transition will play an important role in strengthen, and it should be a strengthening mechanism of aluminum alloy after heat treatment.Based on the results of different tests and under the analysis of our theory guiding, the performances of aluminum alloy will be improved, the strength achieved 520MPa, and it is higher than 450MPa which report in those references, the strength increased more than 15.5%.