Showing 4 results for Aa6061
Mohammad Ali Rasouli, Aboozar Taherizadeh, Mahmood Farzin, Amir Abdolah, Mohammad Reza Niroomand,
Volume 16, Issue 12 (2-2017)
Abstract
Tube spinning or flow forming process is used for manufacturing of seamless tubes widely put into service in advanced industries. The ideal flow for materials entering the deformation zone in this process is extrusion-type flow in axial direction. Very localized deformation zone which is confined by outer materials and forming tools is very important aspect of this process. Therefore, development of defects during the deformation process with undesirable flow of materials can be easily occurred. The main reason of undesirable flow of materials is choosing inappropriate process parameters which results in arising various geometrical and dimensional defects. In this paper, the effects of process parameters on formation and growth of different defects and their correlations with material flow and forming forces in tube spinning of AA6061 was investigated by using design of experiment (DOE) method. The results of experiments show that by applying the optimized values of reduction and feed rate per revolution, these defects can be controlled. Also, by comparing the experimentally measured and theoretically calculated forming forces it can be shown that the larger the deviation of measured forces from calculated ones gets the more severe formation of defects and undesirable materials flow becomes.
M. Nazari, H. Eskandari, M.r. Golbaharhaghighi ,
Volume 20, Issue 3 (2-2020)
Abstract
In this research, friction stir processing was used to produce mono and hybrid surface composite layers of aluminum matrix containing TiB2 and graphene particles. Microstructural evaluation of the samples was performed by optical microscopy and field emission scanning electron microscopy of the composite samples cross-sections. The mechanical properties of the samples were investigated using microhardness and tension tests. Among the samples reinforced with TiB2 and graphene, the samples with 20wt% TiB2 and 1wt% graphene exhibited the highest hardness and strength compared to other samples. Aso, the highest mechanical properties are observed in the sample reinforced with hybrid powders include 20wt% TiB2 and 1wt% graphene. The yield and ultimate strength of the sample increased from 75 and 160MPa (corresponding to the initial 6061 AA) to 191 and 271MPa, respectively. Also, the average hardness of this sample in the stir zone is equal to VHN101 which was significantly higher than the initial alloy (VHN62) and the non-powdered friction-stir sample (VHN71).
M. Ahmadi, H.r. Rezaei Ashtiani ,
Volume 20, Issue 9 (9-2020)
Abstract
The isothermal forging process has the ability to produce complex industrial parts from alloys that do not have high formability, such as aluminum alloys. Eliminating the temperature difference between the part and the die in this method eliminates the problem of cooling the part due to heat transfer to the die. In this study, the hot isothermal forging of AA6061 aluminum alloy in different conditions of process including lubricant type, dimensions and size of primary ingot, temperature and rate of deformation, to produce a complex industrial part numerically and experimentally was investigated. Deform 3D software was used to simulate this process. Comparison of experimental and numerical results showed a good agreement of results. The best dimension of the primary ingot for the studied piece is cylindrical with an initial diameter of 35mm and an initial height of 32mm. Increasing the temperature, reducing the deformation rate and using the appropriate lubricant reduced the amount of required forging force. Reducing the deformation rate from 25-2.5mm/s reduced the required forging force to 1.8 times. Increasing the forging temperature from 380 to 530℃ reduced the amount of forging force about 3.5 times and reducing the hardness of the part about 20%. The results showed that due to the complexity of the forging part, different areas of the part were affected by different strain values, which changes the percentage of secondary phases such as Mg2Si phase in these areas.
Mohsen Azizi , Ali Jabbari , Ehsan Soury , Shayan Dehghan ,
Volume 23, Issue 10 (10-2023)
Abstract
Currently, dissimilar metal joining processes are receiving considerable attention in various industries. The objective is to create composite structures that are both high-strength and lightweight, ultimately reducing the weight of the final product. Researchers have recently proposed friction drilling as a new method for creating joints between dissimilar metal sheets. This innovative technique offers potential advantages in achieving the desired outcomes. In this process, metal sheets are placed on top of each other and simultaneously subjected to friction drilling. As a result, this process not only creates an effective space for tapping but also establishes a frictional joint between the two sheets. Research has shown that preheating up to 350°C can have desirable effects on reducing the gap between the two sheets in the vicinity of the created joint between aluminum and stainless steel using the above-mentioned method. In the upcoming work, the effect of preheating on tool wear in simultaneous friction drilling of aluminum sheet AA6061T6 and stainless steel AISI304L using a tungsten carbide drilling tool has been experimentally analyzed, and the findings indicate that increasing the preheating temperature up to 350°C leads to a 13.77% increase in tool adhesive wear and a 0.46% increase in tool abrasive wear.
