Effect of Shot Peen Forming with Large Balls on Fatigue Resistance of 2024-T351 Aluminum Alloy

2013 ◽  
Vol 816-817 ◽  
pp. 266-270
Author(s):  
Ming Tao Wang ◽  
Yuan Song Zeng ◽  
Jian Qin Shang ◽  
Xia Huang ◽  
Xue Piao Bai

Shot peen forming different from shot peening is a metal forming process widely used in aeronautical industry. Different types of tension-tension fatigue specimens after peen forming were tested. The results show that the fatigue life of specimens peen formed with large balls except edges is 35.4% higher than that of unpeened specimens, while the life of the specimens with whole surface peen formed is 23.2% lower than that of the unpeened specimens. In addition, shot peening specimens which have been peen formed as a surface strengthening way can significantly improve the fatigue resistance. Moreover, when the specimen is peen formed except edges, the position of crack source is from the indentation region to subsurface.

2014 ◽  
Vol 1052 ◽  
pp. 477-481 ◽  
Author(s):  
Ming Tao Wang ◽  
Yuan Song Zeng ◽  
Xue Piao Bai ◽  
Xia Huang

Pre-stress shot peen forming is a metal forming process widely used in aeronautical industry. The test parts of 7150 Al alloy of different thickness were pre-stress shot peen formed. The deformation rule of those parts was investigated by means of changing the peening coverage. The results show that the radius of curvature of the parts will enhance gradually with increasing of the plate’s thickness. In addition, enhancing peening coverage could raise the deformation in the case of that the thickness and peening parameters are unchanged. Furthermore, the minimum radius of curvature of the 8mm plate after saturation pre-stress shot peen forming could reach 499mm.


2010 ◽  
Vol 44-47 ◽  
pp. 2837-2841 ◽  
Author(s):  
Ying Tong

As one of the principal failures, ductile fracturing restricts metal forming process. Cockcroft-Latham fracture criterion is suited for tenacity fracture in bulk metal-forming simulation. An innovative approach involving physical compression experiments, numerical simulations and mathematic computations provides mutual support to evaluate ductile damage cumulating process and ductile fracture criteria (DFC). The results show that the maximum cumulated damage decreases with strain rate rising, and the incremental ratios, that is damage sensitive rate, vary uniformly during the upsetting processes at different strain rates. The damage sensitive rate decreases rapidly, then it becomes stability in a constant 0.11 after true strain -0.85. The true strain -0.85 was assumed as the fracture strain, and the DFC of 6061-T6 aluminum alloy is almost a constant 0.2. According to DFC, the exact fracture moment and position during various forming processes will be predicted conveniently.


2013 ◽  
Vol 773-774 ◽  
pp. 115-118
Author(s):  
Andrzej Gontarz

This paper presents results of theoretical and experimental research works on metal forming process of a hub. A typical technology of forging on hammer of this part with flash was discussed. Two new processes of a hub forging were proposed, characterized by large material savings in comparison with typical technology. The first process is based on forming without flash of a forging with axial cavity. The second one is connected with forming of forging from pipe billet. The realization of these processes is possible at the application of a press with three movable working tools. Theoretical research works were done on the basis of simulations by means of finite element method. Simulations were made mainly in order to determine kinematics of material flow in forging processes and precision of shape and dimensions of obtained products. The first of the proposed processes was experimentally verified and a product of good quality was obtained. Material consumption of the analyzed processes and other factors acting on their effectiveness were also compared.


2013 ◽  
Vol 572 ◽  
pp. 265-268
Author(s):  
Andrzej Gontarz

This paper presents results of theoretical and experimental research works on metal forming process of a hub. A typical technology of forging on hammer of this part with flash was discussed. Two new processes of a hub forging were proposed, characterized by large material savings in comparison with typical technology. The first process is based on forming without flash of a forging with axial cavity. The second one is connected with forming of forging from pipe billet. The realization of these processes is possible at the application of a press with three movable working tools. Theoretical research works were done on the basis of simulations by means of finite element method. Simulations were made mainly in order to determine kinematics of material flow in forging processes and precision of shape and dimensions of obtained products. The first of the proposed processes was experimentally verified and a product of good quality was obtained. Material consumption of the analyzed processes and other factors acting on their effectiveness were also compared.


Procedia CIRP ◽  
2014 ◽  
Vol 18 ◽  
pp. 203-208 ◽  
Author(s):  
J. Enz ◽  
S. Riekehr ◽  
V. Ventzke ◽  
N. Sotirov ◽  
N. Kashaev

2000 ◽  
Vol 123 (4) ◽  
pp. 398-402 ◽  
Author(s):  
Sing C. Tang ◽  
Z. Cedric Xia ◽  
Feng Ren

It is well known in the literature that the isotropic hardening rule in plasticity is not realistic for handling plastic deformation in a simulation of a full sheet-metal forming process including springback. An anisotropic hardening rule proposed by Mroz is more realistic. For an accurate computation of the stress increment for a given strain increment by using Mroz’s rule, the conventional subinterval integration takes excessive computing time. This paper proposes the radial return method to compute such stress increment for saving computing time. Two numerical examples show the efficiency of the proposed method. Even for a sheet model with more than 10,000 thin shell elements, the radial return method takes only 40 percent of the overall computing time by the subinterval integration.


2015 ◽  
Vol 651-653 ◽  
pp. 1153-1158 ◽  
Author(s):  
Bernd Arno Behrens ◽  
Anas Bouguecha ◽  
Milan Vucetic ◽  
Sven Hübner ◽  
Daniel Rosenbusch ◽  
...  

Sheet-bulk metal forming is a manufacturing technology, which allows to produce a solid metal component out of a flat sheet. This paper focuses on numerical and experimental investigations of a new multistage forming process with compound press tools. The complete process sequence for the production of this solid metal component consists of three forming stages, which include a total of six production techniques. The first forming stage includes deep drawing, simultaneous cutting and following wall upsetting. In the second forming stage, flange forming combined with cup bottom ironing takes place. In the last stage of the process sequence, the component is sized. To investigate and to improve process parameters such as plastic strain distribution, resulting dimensions and process forces, FEA is performed. Based on these results the developed process is designed.


Sign in / Sign up

Export Citation Format

Share Document