Microstructure and Hardness of 7055 Aluminum Alloy Processed by Circular Cryogenic-Aging Treatment

2013 ◽  
Vol 575-576 ◽  
pp. 374-377
Author(s):  
Hong Ming Wang ◽  
Guirong Li ◽  
Yun Cai ◽  
Yu Tao Zhao ◽  
Jun Jie Wang ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Aluminum Alloy ◽  
Dislocation Density ◽  
Aging Treatment ◽  
Hardness Test ◽  
Micro Hardness ◽  
Cycle Index ◽  
7055 Aluminum Alloy ◽  
Main Components ◽  
Test Result

7055 aluminum alloy was processed by circular cryogenic-aging treatments for four times. Some characters such as precipitates, dislocation density, crystal structure and micro hardness were studied in detail. It is showed that the sizes of precipitates are decreased from several hundred nanometers to 100nm with the increase of cycle index. The main components are AlZn or AlZnMg phases. The hardness test result illustrates that the micro hardness arrives at 232HV after circular cryogenic-aging treatment for twice. The corresponding precipitates exhibit high density and complex sizes. The sizes are in the range of 50-200nm.

Comparison of Hardness and Microstructure of Cast Wheel and Spoke Wheel Rims of Motorcycles Made of Aluminum Alloy Alloy

2021 ◽  
Vol 892 ◽  
pp. 81-88
Author(s):  
Husaini ◽  
Ali Nurdin ◽  
Abdillah Sofian ◽  
Nuzan Rizki Muhammad
Keyword(s):  
Aluminum Alloy ◽  
Manufacturing Process ◽  
Mechanical Characteristics ◽  
Hardness Test ◽  
Hardness Testing ◽  
Average Hardness ◽  
Vehicle System ◽  
Compressive Loads ◽  
The Difference ◽  
Main Components

The rim is one of the main components in a motorized vehicle system, both two and three wheels. Rim loads when used are dynamic and often even shock. This study aims to study the mechanical characteristics, especially the hardness properties of spoke wheel rims and cast wheel rims made of aluminum alloy used in motorcycles and compare the results. Hardness testing is carried out on the spoke wheel and cast wheel specimens, using the Rockwell method with an identifier of 1/16 ball and a spectrometer used for both microstructure observations. The result of the average hardness test for the spoke wheel is HRB 99.3, while for the cast wheel is HRB 76.5. From the hardness test, it can be concluded that the hardness of the spoke wheel type is higher than the cast wheel type due to the difference in the manufacturing process. Cast wheel rims can withstand a load of 3 tons (30000 N) and the value of rim tension that can be accepted until the fracture is 45.84 MPa. Meanwhile, spoke wheel rims have the ability to withstand smaller compressive loads than cast wheel rims, which are 2 tonnes (20000 N) and the rims can accept the stress of 66.04 MPa until they break.

scholarly journals Influence of Welding Parameters on Weld Formation and Microstructure of Dual-Laser Beams Welded T-Joint of Aluminum Alloy

2011 ◽  
Vol 2011 ◽  
pp. 1-6 ◽  
Author(s):  
Min Li ◽  
Zhuguo Li ◽  
Yong Zhao ◽  
Hao Li ◽  
Yuhua Wang ◽  
...  
Keyword(s):  
Aluminum Alloy ◽  
Hardness Test ◽  
Optical Microscope ◽  
Laser Beams ◽  
Welding Parameters ◽  
Micro Hardness ◽  
Weld Appearance ◽  
Static Tensile ◽  
Clamping Device ◽  
Joint Form

This paper focused on the welding 1.8 mm thick 6061 aluminum alloy plates in T-joint form using dual lasers that introduced by a Nd: YAG laser and a CO2laser with 4043 aluminum filler wire. The effects of welding parameters on the T-joint weld appearance, microstructure and the joint mechanical properties were studied systematically, The influence of welding parameters included the distance between two laser beams, welding speed, laser power and the laser beam offset toward the stringer. The weld appearance, microstructure, hardness of the joint were evaluated by optical microscope and micro-hardness test. A monotonic quasi-static tensile test was conducted by a self-made clamping device to obtain the tensile property of welded joints. At the optimized parameters, the welded T-joint showed good weld appearance without macro defects; the micro hardness of welds ranged from 75 to 85 HV0.3, and the tensile strength was about 254 MPa with the fracture at the heat affected zone on the stringer side.

Characterizations of Electrospark Deposition TA2 Alloy Coating on 7075 Aluminum Alloy Surface

2013 ◽  
Vol 821-822 ◽  
pp. 873-876
Author(s):  
Ming Wei Wang ◽  
Wen Xin ◽  
Xiu Jun Zhao ◽  
Qin Yi Ma ◽  
Shu Li
Keyword(s):  
Aluminum Alloy ◽  
Electrode Materials ◽  
Hardness Test ◽  
Alloy Coating ◽  
7075 Aluminum Alloy ◽  
Micro Hardness ◽  
X Ray Diffraction ◽  
Electrospark Deposition ◽  
Gradient Distribution ◽  
Electrical Pulses

Electro-spark deposition (ESD) is a microwelding process that utilizes short duration of electrical pulses to deposit electrode materials to a metallic substrate. In this paper, taking TA2 bar as electrode, a deposition layer of thickness up to 40μm was built up to on 7075 aluminum alloy substrate by means of ESD. The deposition layer is metallurgical bonded to the substrate. The microstructure, phase composition, and micro-hardness of TA2 coating were investigated using scanning electron microscopy (SEM), X-ray diffraction (XRD) and micro-hardness test. The microstructure of the coating was mainly composed of TiN phase, Al3Ti phase, AlN phase and Al phase. Its micro-hardness reached 295 HV0.05, about 2 times as high as that of the substrate. The hardness at the cross-section of the entire deposition layer showed a gradient distribution.

Evaluation of the Resistance of Individual Si Die to Cracking

1998 ◽  
Author(s):  
R. Berriche ◽  
R.K. Lowry ◽  
M.I. Rosenfield
Keyword(s):  
Thermal Cycling ◽  
Hardness Test ◽  
Mechanical Stresses ◽  
Test Method ◽  
Processing Conditions ◽  
Micro Hardness ◽  
Test Methodology ◽  
Vickers Micro Hardness

Abstract The present work investigated the use of the Vickers micro-hardness test method to determine the resistance of individual die to cracking. The results are used as an indicator of resistance to failure under the thermal and mechanical stresses of packaging and subsequent thermal cycling. Indentation measurements on die back surfaces are used to determine how changes in wafer backside processing conditions affect cracks that form around impressions produced at different loads. Test methodology and results obtained at different processing conditions are discussed.

INFLUENCE OF AGING ON THE HARDENABILITY OF 7055 ALUMINUM ALLOY THICK PLATE

2012 ◽  
Vol 48 (3) ◽  
pp. 343 ◽  
Author(s):  
Shengdan LIU ◽  
Chengbo LI ◽  
Yunlai DENG ◽  
Xinming ZHANG
Keyword(s):  
Aluminum Alloy ◽  
Thick Plate ◽  
7055 Aluminum Alloy

Micro-Hardness and Morphology of LDPE Influenced by Beta Radiation

2014 ◽  
Vol 606 ◽  
pp. 253-256 ◽  
Author(s):  
Martin Ovsik ◽  
Petr Kratky ◽  
David Manas ◽  
Miroslav Manas ◽  
Michal Stanek ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Hardness Test ◽  
Polymer Materials ◽  
Beta Radiation ◽  
Micro Hardness ◽  
X Ray Diffraction ◽  
Depth Sensing ◽  
Surface Layers ◽  
Hardness Values ◽  
Different Doses

This article deals with the influence of different doses of Beta radiation to the structure and mico-mechanical properties of Low-density polyethylene (LDPE). Hard surface layers of polymer materials, especially LDPE, can be formed by radiation cross-linking by β radiation with doses of 33, 66 and 99 kGy. Material properties created by β radiation are measured by micro-hardness test using the DSI method (Depth Sensing Indentation). Individual radiation doses caused structural and micro-mechanical changes which have a significant effect on the final properties of the LDPE tested. The highest values of micro-mechanical properties were reached at radiation dose of 66 and 99 kGy, when the micro-hardness values increased by about 21%. The changes were examined and confirmed by X-ray diffraction.

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.

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