Relationship between Saturation Curve and Peening Parameters for Aerospace Shot Peening Process

2007 ◽  
Vol 561-565 ◽  
pp. 965-968
Author(s):  
Chi Kong Huang ◽  
Chau Chen Torng ◽  
Hsien Ming Chang
Keyword(s):  
Fatigue Life ◽  
Fatigue Strength ◽  
Shot Peening ◽  
Mass Production ◽  
Saturation Curve ◽  
Statistical Methodology ◽  
Saturation Point ◽  
Verification Period ◽  
Machine Parts ◽  
The Relationship

The shot peening process can improve the fatigue strength of machine parts of aero structures. Due to the strength requirement of aircraft, the shot peening is widely used in the manufacturing process. Most of shot peening parts peened after penetrate inspection to ensure no defect and crack on the surface, and then peen the shots on the surface of machine parts to increase the fatigue life. During the first article verification period, the saturation curve has to be created. The peening parameters of mass production would base on the peening parameters of saturation point of the saturation curve. By using statistical methodology to analysis saturation curve of shot peening process, this study tries to find the relationship between saturation curve and relative peening parameters, such as peening time, air pressure. The results of this analysis can provide an efficient and economical approach for the process engineer and technician to develop the new shot peening process.

The Effect of Shot Peening on the Surface Topography and Fatigue Strength of Selected Sheets

2015 ◽  
Vol 818 ◽  
pp. 19-22
Author(s):  
Łukasz Bąk ◽  
Magdalena Bucior ◽  
Felix Stachowicz ◽  
Władysław Zielecki
Keyword(s):  
Fatigue Life ◽  
Fatigue Strength ◽  
Shot Peening ◽  
Experimental Tests ◽  
Special Treatment ◽  
Surface Layers ◽  
Impact Bending ◽  
Improve Fatigue Strength ◽  
Compressive Residual Stresses ◽  
Improve Fatigue

Numerous investigations have been performed in an attempt to improve fatigue strength of materials by creating compressive residual stresses in the surface layers as a result of the shot peening process. For example, during exploitation of the separating screener, some parts of screen sieve plate situated near the fixed edge undergo the largest deformation caused by impact bending and need special treatment. In this paper, the results of experimental tests are presented to analyse the effect of micro shot peening on surface layer characteristics and fatigue strength of steel sheet specimens. The effect of shot peening is more visible when fatigue life is taking into account. Thus, the use of shot peening of sheet surface made it possible to increase fatigue life of screener sieve.

scholarly journals Effect of Carburizing and Nitriding on Fatigue Properties of 18Cr2Ni4WA Steel in Very High Cycle Fatigue Regime

2021 ◽  
Vol 45 (3) ◽  
pp. 207-215
Author(s):  
Zhenduo Sun ◽  
Dongbo Hou ◽  
Wei Li
Keyword(s):  
Fatigue Life ◽  
Fatigue Strength ◽  
High Cycle Fatigue ◽  
Fatigue Properties ◽  
Cycle Fatigue ◽  
Internal Defect ◽  
Surface Fatigue ◽  
Very High Cycle Fatigue ◽  
The Relationship ◽  
Very High

The work aims to study the influence of carburizing and nitriding on fatigue properties of 18Cr2Ni4WA high strength steel in very high cycle fatigue regime. Very high cycle fatigue tests were carried out on 18Cr2Ni4WA Steel after carburizing and nitriding respectively. The micro morphology of fatigue fracture was observed by scanning electron microscope, the failure mode and failure mechanism were discussed. The relationship between fatigue life and defect size, FGA size, fish eye size of fracture was analyzed. The characteristic size of defects is evaluated by Gumbel, Weibull and GEV distribution functions, and a modified Akiniwa fatigue life prediction model considering the relationship between FGA size and inclusion size was established. The results showed that, nitriding and carburizing treatment improve the surface fatigue limit of the steel. The fatigue life decreases with the increase of internal defect size and FGA size. After carburizing and nitriding treatment, the internal fatigue strength of the specimen decreases slightly. When the failure probability is 99%, the internal defect sizes of nitrided specimens calculated by Weibull, Gumbel and GEV distributions are 141.5 μm, 148.4 μm and 211.7 μm respectively. The calculated internal defect sizes of carburized specimens are 47 μm, 67.8 μm and 40 μm respectively. Compared with the experimental data, the fatigue strength predicted by GEV is the most appropriate. carburizing and nitriding treatment can improve the surface fatigue strength of 18Cr2Ni4WA steel, but slightly reduce the internal fatigue strength. The prediction result of the new model is conservative when the failure probability is 99%, which is suitable for engineering application.

scholarly journals The Effect of Baking Heat Treatment on the Fatigue Strength and Life of Shot Peened 4340M Landing Gear Steel

Materials ◽  
2020 ◽  
Vol 13 (24) ◽  
pp. 5711
Author(s):  
Seok-Hwan Ahn ◽  
Jongman Heo ◽  
Jungsik Kim ◽  
Hyeongseob Hwang ◽  
In-Sik Cho
Keyword(s):  
Heat Treatment ◽  
Fatigue Life ◽  
Fatigue Strength ◽  
Fatigue Limit ◽  
Shot Peening ◽  
High Cycle Fatigue ◽  
Landing Gear ◽  
Cycle Fatigue ◽  
Heat Treated ◽  
Ultrasonic Fatigue

In this study, the effect of baking heat treatment on fatigue strength and fatigue life was evaluated by performing baking heat treatment after shot peening treatment on 4340M steel for landing gear. An ultrasonic fatigue test was performed to obtain the S–N curve, and the fatigue strength and fatigue life were compared. The micro hardness of shot peening showed a maximum at a hardened depth of about 50 μm and was almost uniform when it arrived at the hardened depth of about 400 μm. The overall average tensile strength after the baking heat treatment was lowered by about 80–111 MPa, but the yield strength was improved by about 206–262 MPa. The five cases of specimens showed similar fatigue strength and fatigue life in high cycle fatigue (HCF) regime. However, the fatigue limit of the baking heat treated specimens showed an increasing tendency rather than that of shot peening specimens when the fatigue life was extended to the very high cycle fatigue (VHCF) regime. The effect of baking heat treatment was identified from improved fatigue limit when baking heat was used to treat the specimen treated by shot peening containing inclusions. The optimum temperature range for the better baking heat treatment effect could be constrained not to exceed maximum 246 °C.

The Relationship Between Design, Processing and Shot Peening on Wheel Plate Failures

2014 ◽  
Author(s):  
Steven L. Dedmon
Keyword(s):  
Fatigue Life ◽  
Residual Stresses ◽  
Cold Rolling ◽  
Shot Peening ◽  
Cyclic Stresses ◽  
Compressive Stresses ◽  
Freight Car ◽  
The Relationship ◽  
Fatigue Failures ◽  
Improve Fatigue

Wheel plate failures occur rarely in North American freight car service. When they do occur, derailments are a likely result. Shot peening has been used to improve fatigue life for more than 80 years and the efficacy of the process is now undisputed in reducing fatigue failures of parts subjected to high levels of cyclic stresses. The introduction of residual compressive stresses from shot peening is acknowledged as the reason for the improvement in fatigue life; comparable processes such as cold rolling, are successful for the same reason. Since residual stresses are so important to fatigue life, then design and processing prior to shot peening should have an equally important role. This investigation demonstrates some of the variables which are important to producing wheels resistant to plate fatigue failures.

scholarly journals Cumulative Fatigue damage of AA7075-T6 under Shot Peening and Ultrasonic Surface Treatments

2021 ◽  
Vol 14 (1) ◽  
pp. 1-10
Author(s):  
Marwa S. Mahammed ◽  
Hussain J. Alalkawi ◽  
Saad T. Faris
Keyword(s):  
Fatigue Life ◽  
Fatigue Strength ◽  
Fatigue Damage ◽  
Shot Peening ◽  
Endurance Limit ◽  
Mechanical Design ◽  
Ultrasonic Impact Treatment ◽  
Sample Group ◽  
Cumulative Fatigue Damage ◽  
Fatigue Endurance

One of the important aspects of mechanical design is improving fatigue life.; In this work, the effect of Ultrasonic impact treatment (UIP) and shot peening (SP)on constant cumulative fatigue life and fatigue strength of AA7075-T6 were studied; The sample group was machined and primed, and some specimens were treated using ultrasonic impact therapy (UIT) with one line of peening. Fatigue experiments were conducted under constant and variable amplitude (R=-1) at ambient temperature to determine the fatigue life of the S-N curve and fatigue strength during treatment 3.46% and 8.57% at 107 cycles for (UIT) and (SP). Cumulative fatigue damage testing was carried out for two steps loading it is observed that the fatigue life for SP and UIP treated specimens was improved compared to the unpeeled results. The fatigue endurance limit was enhanced by 35% for UIT and 54% for SP. The fatigue life for both treatments was much improved compared to as-received metal. These results also show a strong tendency of increasing fatigue strength after application of (UIT) and (SP) with an increase in mechanical properties of the material used.

An Analysis of the Influence of Cutting Parameters on the Turning Process on the Fatigue Life of Aluminum Alloy UNS A92024-T351

2012 ◽  
Vol 498 ◽  
pp. 19-24 ◽  
Author(s):  
Alvaro Gómez ◽  
A. Sanz ◽  
Mariano Marcos Bárcena
Keyword(s):  
Aluminum Alloy ◽  
Fatigue Life ◽  
Fatigue Strength ◽  
Surface Condition ◽  
Cutting Parameters ◽  
Structural Elements ◽  
Turning Process ◽  
Machining Processes ◽  
Preliminary Study ◽  
The Relationship

Generally, metal structural elements of aircraft are placed in zones of critical load; in most cases, these elements are manufactured by machining processes. The fatigue life of these components is an important dynamic property that may be strongly affected by the surface condition produced during machining. In this paper a preliminary study of the influence of cutting parameters on fatigue strength of parts machined in aeronautical aluminum alloy UNS A92024-T351 has been carried out. Special attention has been provided to the relationship with surface finish evaluated through the roughness average.

scholarly journals Assessment of the Impact of Shot Peening on the Fatigue Life of a Compressor Blade Subjected to Resonance Vibrations

2020 ◽  
Author(s):  
Arkadiusz Bednarz ◽  
Wojciech Misiołek
Keyword(s):  
Fatigue Life ◽  
Shot Peening ◽  
Geometric Model ◽  
Fatigue Analysis ◽  
Compressor Blade ◽  
Resonant Vibrations ◽  
Equivalent Stresses ◽  
Resonance Vibrations ◽  
The Impact ◽  
The Relationship

The publication presents the assessment of the influence of surface treatment such as shot-peening on the fatigue life of a compressor blade exposed to resonant vibrations. As part of the work, a geometric model of the blade was developed and a numerical modal and fatigue analysis were performed. The fatigue analysis was based on the Manson-Coffin-Basquin and Ramberg-Osgood models. As part of the work, the influence of different values of residual stresses on the results of fatigue life was determined. Additionally, the location of the highest equivalent stresses was established. The obtained results of the numerical analyzes were compared with the results presented in the scientific literature. An additional aim of the study was to determine the size of the grains at various points of the blade as well as the thickness of the layer plasticized as a result of peening. The obtained results are presented in the form of tables and charts. The relationship between the location of the highest values of equivalent stresses and the thickness of the plasticized layer was determined. The explanation of the effect of shot peening on the increase in fatigue life of the blade was proposed.

scholarly journals Effect of Oil – Corrosion on Tensile and Fatigue S-N Curve Properties of AA6061-T6

2021 ◽  
Vol 39 (3A) ◽  
pp. 407-414
Author(s):  
Hussain J.M. Al-Alkawi ◽  
Ghgada A. Aziz ◽  
Shmoos R. Mazel
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Fatigue Life ◽  
Fatigue Strength ◽  
Corrosion Fatigue ◽  
Shot Peening ◽  
Fatigue Behavior ◽  
Surface Layers ◽  
Compressive Residual Stresses ◽  
Behavior Strength

The present study described the effect of shot peening on mechanical properties and rotating corrosion –fatigue behavior (strength and life) of AA6061-T6. Ultimate tensile strength (UTS) and yield stress (YS) were reduced by 4.6% and 1.24% when immersing the tensile samples in crude oil for 60 days. The values of (UTS) and (YS) were raised from 307 to 316 MPa and from 248 to 254 MPa respectively when treated for 10 min. shot peening (SP). Hardness of oil corrosion samples dropped due to pitting corrosion and slightly raised for SP prior to corrosion samples. Oil corrosion reduced the fatigue strength by (-1.25%). This percentage was enhanced due to SP to 2.377%. SP significantly increased the rotating fatigue life by a factor of 1.19 and 1.3 at (UTS) and (Ys) loads respectively. (SP) technique improved corrosion-fatigue resistance due to producing compressive residual stresses at surface layers.

Increasing the fatigue strength of high-strength steel parts by repeated treatment with shot peening

2020 ◽  
pp. 79-82
Author(s):  
G.N. Kravchenko ◽  
K.G. Kravchenko
Keyword(s):  
Fatigue Strength ◽  
Shot Peening ◽  
High Strength Steel ◽  
High Strength ◽  
Resource Recovery ◽  
Repeated Treatment ◽  
Multiple Processing

The effectiveness of multiple hardening by shot peening of samples made of «30ХГСН2А» high-strength steel to increase their fatigue strength is experimentally established. Repeated hardenings allow not only to restore the original durability and even significantly increase it. Keywords fatigue strength, durability, resource recovery, multiple processing by shot peening, repeated hardening, high-strength steel. [email protected]

Sign in / Sign up

Export Citation Format

Share Document