scholarly journals Investigation on Compressive Formability and Microstructure Evolution of 6082-T6 Aluminum Alloy

Metals ◽  
2020 ◽  
Vol 10 (4) ◽  
pp. 469
Author(s):  
Zhouli Xu ◽  
Huijuan Ma ◽  
Ning Zhao ◽  
Zhili Hu
Keyword(s):  
Aluminum Alloy ◽  
Treatment Time ◽  
Heating Temperature ◽  
Solution Treatment ◽  
Heating Time ◽  
Strengthening Effect ◽  
Forming Process ◽  
Production Time ◽  
Precipitated Phase ◽  
First Choice

The 6xxx aluminum alloy is the first choice for automotive lightweight forgings due to its excellent performance, high strength and low weight. The production time of current aluminum alloy forging generally exceeds 10 h. To reduce the production time of traditional aluminum alloy forgings, 6082-T6 aluminum alloy is used in the forming process. The effects of different heating temperatures (200 °C, 300 °C, and 400 °C) and deformation degrees (30%, 50%, and 70%) on the deformability and properties of 6082-T6 billets have been investigated. The results show that when the heating temperature is higher than 300 °C, the compressive deformation resistance obviously decreases with increasing strength. With compression at 200 °C and 70% deformation with short heating time, the strength of the sample is close to the T6 (solution treatment and artificial aging) state. A large number of dislocations and subgrains were introduced due to the compression deformation, and their amounts decreased as the heating temperature increased. The size of the precipitated phase β′′ slightly grows under a heating temperature of 200 °C. However, when the heating temperature is higher than 300 °C, the precipitated phase gradually changes from β′′, which is optimal for the strengthening effect, to β′ and β, which offer weaker strengthening. Therefore, under a lower heating temperature of 200 °C for 5 min, a large number of dislocations are introduced with the β′′ precipitated phase, leading to higher strength with less heat treatment time.

scholarly journals Study on Ultra-High Temperature Contact Solution Treatment of Al–Zn–Mg–Cu Alloys

Metals ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 842
Author(s):  
Wenming Jin ◽  
Jianhao Yu ◽  
Zhiqiang Zhang ◽  
Hongjie Jia ◽  
Mingwen Ren
Keyword(s):  
Heating Temperature ◽  
Solution Treatment ◽  
Strengthening Mechanism ◽  
Heating Time ◽  
Solution Time ◽  
Solution Temperature ◽  
Second Phase ◽  
Total Strength ◽  
Cu Alloys ◽  
Short Heating Time

Contact solution treatment (CST) of Al–Zn–Mg–Cu alloys can shorten solution time to within 40 s in comparison with 1800 s with traditional solution treatment using a heating furnace. Heating temperature is the key factor in solution treatment. Considering the short heating time of CST, the ultra-high solution temperature over 500 °C of Al–Zn–Mg–Cu alloys was studied in this work. The effects of solution temperatures on the microstructures and the mechanical properties were investigated. The evolution of the second phases was explored and the strengthening mechanisms were also quantitatively evaluated. The results showed that solution time could be reduced to 10 s with the solution temperature of 535 °C due to the increasing dissolution rate of the second phase and the tensile strength of the aged specimen could reach 545 MPa. Precipitation strengthening was the main strengthening mechanism, accounting for 75.4% of the total strength. Over-burning of grain boundaries occurred when the solution temperature increased to 555 °C, leading to the deterioration of the strength.

Numerical Simulation and Process Optimization of Automotive Friction Materials in Warm Pressing Forming

2013 ◽  
Vol 788 ◽  
pp. 57-60
Author(s):  
Chun Cao ◽  
Chun Dong Zhu ◽  
Chen Fu
Keyword(s):  
Process Optimization ◽  
Heating Temperature ◽  
Maximum Energy ◽  
Heating Time ◽  
Product Performance ◽  
Forming Process ◽  
Friction Materials ◽  
Forming Technology ◽  
The Relationship ◽  
Temperature Heating

Warm pressing forming technology has been gradually applied to the forming of automotive friction materials. How to ensure product performance to achieve the target at the same time achieve the maximum energy saving is the research focus of this study. In this paper, by using finite element method, the field of automotive friction materials in warm pressing forming was analyzed, reveals the relationship between the temperature field and the heating temperature/heating time. Furthermore, the energy consumption was analyzed and compared it with hot pressing forming process. The results will have significant guiding to the process optimization in warm pressing forming.

scholarly journals Effects of the Mg/Si Ratio on Microstructure, Mechanical Properties, and Precipitation Behavior of Al–Mg–Si–1.0 wt %-Zn Alloys

Materials ◽  
2018 ◽  
Vol 11 (12) ◽  
pp. 2591 ◽  
Author(s):  
Yong Li ◽  
Guanjun Gao ◽  
Zhaodong Wang ◽  
Hongshuang Di ◽  
Jiadong Li ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Volume Fraction ◽  
Solution Treatment ◽  
Hardness Test ◽  
Strengthening Effect ◽  
Precipitation Behavior ◽  
Scanning Calorimetry ◽  
First Choice ◽  
The Matrix ◽  
Zn Alloys

Aluminum alloys are widely used as first-choice materials for lightweight automotive applications. It is important that an alloy have a balance between strength and formability. In this study, the alloys were melted, cast, hot rolled, and cold rolled into 1 mm-thick sheets. The microstructure, mechanical properties, and precipitation behavior of Al–Mg–Si–1.0 wt %-Zn alloys with Mg/Si ratios of 0.5, 1, and 2 after solution treatment were studied using optical and electron microscopy, a tensile test, the Vickers hardness test, and differential scanning calorimetry. The results showed that a high density and number of Al–Fe–Si particles were observed in the matrix, thus causing the formation of more homogeneous and smaller recrystallized grains after treatment with the solution. In addition, a higher volume fraction of cubeND and P-types texture components formed during solution treatment. Also, a high r value and excellent deep drawability were achieved in the medium-Mg/Si-ratio alloy. The formation of denser strengthening precipitates led to a better paint-bake hardening effect in comparison with the other two alloys. Furthermore, the precipitation kinetics were enhanced by the addition of Si, and the addition of Zn did not alter the precipitation sequence of the Al–Mg–Si alloy. The dual-phase strengthening effect was not achieved in the studied alloys during paint-bake treatment at 175 °C.

scholarly journals Grain Coarsening and Texture Evolution of Pre-Stretched 2219 Aluminum Alloy Sheets during Subsequent Solution Treatment

Metals ◽  
2019 ◽  
Vol 9 (5) ◽  
pp. 530 ◽  
Author(s):  
Lihui An ◽  
Jiguang Li ◽  
Shijian Yuan
Keyword(s):  
Aluminum Alloy ◽  
Grain Growth ◽  
Texture Evolution ◽  
Solution Treatment ◽  
Optical Microscope ◽  
Stretch Forming ◽  
Forming Process ◽  
Deformation Degree ◽  
Grain Structures ◽  
2219 Aluminum Alloy

During the two-pass stretch forming process for manufacturing of thin-walled aluminum alloy sheet components, abnormal grain growth may happen if an improper pre-deformation degree was conducted before solution heat treatment, which is negative to the performance and surface quality of the final components. In order to overcome this problem, the effect of pre-stretching deformation was investigated on the change of grain structures of 2219 aluminum alloy sheets. The 2219 aluminum alloy sheets were pre-stretched with various deformation degrees, and then were heated to 540 °C for about 50 min for solution treatment. The grain structures before and after solution treatment were characterized using an optical microscope (OM) and electron back scattering diffraction (EBSD). Results show that the grains grew up gradually during the solution treatment with an increase of pre-stretching. The critical pre-stretching degree is about 3%. Once the pre-deformation exceeds 3%, the grain growth is significant, especially when it reaches 5%. Moreover, the pre-stretching has little influence on the orientation distribution. Some near a copper texture {112}<111> were generated as the pre-stretching degree was increased to 5%. All the results suggest that the pre-stretching before solution treatment cannot be larger than 3% in the two-pass stretch forming of a 2219 aluminum sheet.

Deformation Behavior of Aluminum Alloy Tube in Semi-Dieless Metal Bellows Forming Process with Local Heating Technique

2014 ◽  
Vol 936 ◽  
pp. 1742-1746 ◽  
Author(s):  
Zi Cheng Zhang ◽  
Kenichi Manabe ◽  
Tsuyoshi Furushima ◽  
Kazuo Tada ◽  
Osamu Sasaki
Keyword(s):  
Aluminum Alloy ◽  
Compression Ratio ◽  
Deformation Behavior ◽  
Heating Temperature ◽  
Local Heating ◽  
Manufacturing Cost ◽  
Forming Process ◽  
Alloy Tube ◽  
Metal Bellows ◽  
Aluminum Alloy Tube

The metal bellows are used in a large number of industrial applications for their flexile and elastic properties. For the traditional manufacturing methods for metal bellows, the dies and (or) tools are required. It is inconvenient to change the shape of metal bellows and also leads to the high cost. To reduce the manufacturing cost and produce the metal bellows with various shapes, the semi-dieless metal bellows forming process was proposed. The deformation behavior of aluminum alloy tube in semi-dieless bellows forming process was investigated in the study. The effects of compression ratio, heating length on the convolution height, pitch of bellows during the semi-dieless bellows forming process were studied. The results showed that the deformation conditions of semi-dieless forming process have significant influences on the shape of aluminum alloy bellows and deformation behavior of aluminum alloy tube in the forming process. The increase of compression ratio, heating temperature and heating length resulted in the increase of pitch and decrease convolution height of aluminum alloy metal bellows.

scholarly journals Evaluation of Ultrasonic Nonlinear Characteristics in Heat-Treated Aluminum Alloy (Al-Mg-Si-Cu)

2013 ◽  
Vol 2013 ◽  
pp. 1-6 ◽  
Author(s):  
JongBeom Kim ◽  
Kyung-Young Jhang
Keyword(s):  
Aluminum Alloy ◽  
Elastic Properties ◽  
Second Harmonic ◽  
Heating Temperature ◽  
Ultrasonic Method ◽  
Heating Time ◽  
Nonlinear Parameter ◽  
Nonlinear Characteristics ◽  
Heat Treated ◽  
Frequency Components

The nonlinear ultrasonic technique has been known to be more sensitive to minute variation of elastic properties in material than the conventional linear ultrasonic method. In this study, the ultrasonic nonlinear characteristics in the heat-treated aluminum alloy (Al-Mg-Si-Cu) have been evaluated. For this, the specimens were heat treated for various heating period up to 50 hours at three different heating temperatures: 250°C, 300°C, and 350°C. The ultrasonic nonlinear characteristics of each specimen were evaluated by measuring the ultrasonic nonlinear parameterβfrom the amplitudes of fundamental and second harmonic frequency components in the transmitted ultrasonic wave. After the ultrasonic test, tensile strengths and elongations were obtained by the tensile test to compare with the parameterβ. The heating time showing a peak in the parameterβwas identical to that showing critical change in the tensile strength and elongation, and such peak appeared at the earlier heating time in the higher heating temperature. These results suggest that the ultrasonic nonlinear parameterβcan be used for monitoring the variations in elastic properties of aluminum alloys according to the heat treatment.

scholarly journals Characterization of Precipitation in 7055 Aluminum Alloy by Laser Ultrasonics

Metals ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 275
Author(s):  
Zhenge Zhu ◽  
Hao Peng ◽  
Yacheng Xu ◽  
Xueyong Song ◽  
Jinrong Zuo ◽  
...  
Keyword(s):  
Aluminum Alloy ◽  
Electron Microscope ◽  
Laser Ultrasonics ◽  
Precipitate Size ◽  
Destructive Testing ◽  
Laser Ultrasonic ◽  
Precipitated Phase ◽  
Transmission Electron ◽  
7055 Aluminum Alloy ◽  
The Time Domain

After different rolling conditions, four 7055 aluminum alloy samples with different precipitation sizes were measured by scanning electron microscope, transmission electron microscope and laser ultrasonic. The attenuation coefficients of ultrasound measured by laser ultrasonic were calculated in the time domain, frequency domain and wavelet denoising, respectively. The relationship between the precipitate size and attenuation coefficient was established. The results show that the attenuation of the ultrasonic wave is related to the size of the precipitated phase; this provides a new method for rapid non-destructive testing of the precipitation of aluminum alloys.

Changes in Microstructure of Biomedical Co-Cr-Mo-C Alloys with Solution Treating and Aging

2010 ◽  
Vol 89-91 ◽  
pp. 377-382 ◽  
Author(s):  
S. Mineta ◽  
Shigenobu Namba ◽  
Takashi Yoneda ◽  
Kyosuke Ueda ◽  
Takayuki Narushima
Keyword(s):  
Solution Treatment ◽  
Heating Time ◽  
Treatment Temperature ◽  
Vacuum Furnace ◽  
Solution Treatment Temperature ◽  
Precipitate Dissolution ◽  
Heat Treated ◽  
M23c6 Type ◽  
Type Carbide ◽  
Time Required

Microstructural changes occurring in biomedical Co-Cr-Mo alloys with three carbon levels due to solution treatment and aging were investigated. Ingots of Co-Cr-Mo alloys with three different carbon levels were prepared by vacuum furnace melting; their chemical composition was Co-28Cr-6Mo-xC (x = 0.12, 0.25 and 0.35 mass%). Precipitates were electrolytically extracted from as-cast and heat-treated alloys. An M23C6 type carbide and a phase were detected as precipitates in as-cast Co-28Cr-6Mo-0.12C alloy, and an M23C6 type carbide and an  phase (M6C-M12C type carbide) were detected in as-cast Co-28Cr-6Mo-0.25C and Co-28Cr-6Mo-0.35C alloys. Only the M23C6 type carbide was detected during solution treatment. Complete precipitate dissolution occurred in all the three alloys after solution treatment. The holding time required for complete precipitate dissolution increased with increasing carbon content and decreasing solution treatment temperature. Complete precipitate dissolution occurred in the Co-Cr-Mo-C alloys solution treated at 1523 K for 43.2 ks; they were then subjected to aging from 873 to 1473 K for a heating time up to 44.1 ks after complete precipitate dissolution in solution treatment at 1523 K for 43.2 ks. The M23C6 type carbide with a grain size of 0.1–3 m was observed after aging. A time-temperature-precipitation diagram of the M23C6 type carbide formed in the Co-28Cr-6Mo-0.25C alloy was plotted.

Sign in / Sign up

Export Citation Format

Share Document