Print ISSN: 1681-6900

Online ISSN: 2412-0758

Keywords : Shot peening

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

Hussain J.M. Al-Alkawi; Ghgada A. Aziz; Shmoos R. Mazel

Engineering and Technology Journal, 2021, Volume 39, Issue 3A, Pages 407-414
DOI: 10.30684/etj.v39i3A.298

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.

Fatigue Life and Surface Hardening Investigation of Aluminum Shot Peening Process

Kayser A. Ameen

Engineering and Technology Journal, 2018, Volume 36, Issue 6A, Pages 672-676
DOI: 10.30684/etj.36.6A.12

Two different tests are used in order to analyze the shot peening foraluminum 6061-T6 alloys. Stress amplitude versus fatigue life (S-N curves) are established experimentally using different shot peening ball size (three diameters of balls are used in this paper are 1.5, 3, and 3.5 mm). Also the hardening via Vickers hardnessis evaluated due to shot peening experimentally and by ANSYS software, the three dimensional finite element model of a square plate shot by ball is demonstrates the application of shot peened of hardening surface.The influences of the ball’s diameter on the hardening and S-N curves are studied. The results showed that the fatigue strength is increased when increasing the ball diameter. The higher strength was obtained when using the ball diameter of (3.5 mm) compared to the other diameters (1.5 and 3 mm). Good agreement of hardening results is evident between experimental and Ansys results with average discrepancy 3.6%

Electrical Laser Alarm System for Controlling the Buckling Failure of 304 Stainless Steel under Shot Peening Treatment

A. I. Hussain; F. A. K. Fattah; A. J. Alkawi; H. J. M. Al

Engineering and Technology Journal, 2017, Volume 35, Issue 5, Pages 516-524
DOI: 10.30684/etj.35.5A.11

The purpose of this paper is to design and manufacture the electrical laser alarm system to assess the buckling failure of 304 stainless steel column and to estimate the critical buckling load (Pcr) under increasing compressive load without shot peening (WSP) and with shot peening (SP). The evaluation of the critical buckling load (Pcr ) was done experimentally and theoretically for long and intermediate pinned – fixed columns. The experimental results revaled that 25 min. shot peening time (SPT) improved the critical buckling load (Pcr ) by 13.3% - 15.39% improvement percentage (IP) for long columns while 18.51% - 23.07% for intermediates. Also it was observed that reducing the effective length (Leff ) resulting in increasing the effect of 25 min. shot peening time (SPT) and kept constant when effective length (Leff ) larger than 200mm. The difference percentage (DP) obtained from theoretically and experimentally comparison between the critical buckling load (Pcr ) was 33.33 to 41.18 for without shot peening and 23.07 to 33.34 for 25 min. shot peening time (SPT) based on Euler and Johnson theories for both long and intermediate columns. Also it was revaled that increasing the slenderness ratio (S.R) reducing the critical buckling load (Pcr) for both columns and both conditions of testing without shot peening (WSP) and shot peening (SP).

Effect of Surface Roughness and Shot Peening Treatments on The Mechanical Properties of Aluminum Alloy 2024 – T4

Alalkawi H. J. M; Ameer Tofan Shafiq; Mohammed khalouk al-azzawi

Engineering and Technology Journal, 2014, Volume 32, Issue 10, Pages 2386-2393

The objective of the present paper is to investigate the effect of surface roughness on mechanical properties of aluminum alloy 2024-T4. This paper describes the effect of surface roughness at values of ( 0.1 , 3.5 , 8 ) μm on hardness and yield strength and also estimate the effect of shot peening on the yield strength at period time of ( 5 , 10 , 15 , 20 , 25 ) min. The obtained results show that the low roughness improved the mechanical properties by 15.7% and also the low roughness is better than the shot peening treatments by 5.3% because the low roughness make surface more coherent. Empirical equations are formulated based on the experimental results to evaluate the yield strength with the surface roughness and the hardness.

Sy= 394.3 ( Ra + 1.35 ) -0.1356
Sy = 1 / 2.2227(10)-2 - 1.32(10)-4 HV

Experimental Study of the Effect of Shot Peening on Elevated Temperature Fatigue Behavior of 7075-T651 Al. alloy

Hussain J. Al-Alkawi; Shakir Sakran Hassan; Salah F. Abd-El-Jabbar

Engineering and Technology Journal, 2013, Volume 31, Issue 3, Pages 416-433

There is a general interest in increasing the fatigue life of materials. Shot peening is the process commonly used in order to increase the fatigue strength and life of 7075-T651. The effect of a combination of processes, fatigue-creep interaction and shot peening has not been thoroughly investigated so far. The aim of the present investigation was whether further improvements can be achieved by a comb/*ination of the two treatments. Two level experiments (cumulative fatigue damage programe) were used in order to determine the optimal set of process. It was found that the combination of shot peening and fatigue-creep interaction could be applied successfully in order to increase fatigue life for some specimens. Results of variable loading test clearly indicate that Miner rule does not give accurate and reliable predictions on fatigue lives.

The Effect of Shot Peening and Residual Stresses on Cumulative Fatigue Damage

Hussain J. M. Alalkawi; Qusay Khalid Mohammed; Waleed Sadun Al-Nuami

Engineering and Technology Journal, 2010, Volume 28, Issue 15, Pages 5055-5070

A series of constant and cumulative fatigue tests under the effect of shot peening were conducted for two aluminum alloys 2024 and 5052. Three unpeed specimens were tested for each alloy under low-high stress levels (120-280 MPa) for 2024 aluminum alloy and (40-90 MPa) for 5052 aluminum alloy at room temperature and stress ratio R= -1. Other specimens were exposed to shot peening with different blasting time before the cumulative fatigue testing. It is found for 2024 Al alloy that as the shot peening time increases the cumulative fatigue life is improved but above 10 min. the life is reduced. For 5052 Al alloy the cumulative fatigue life is reduced as shot peening time increases

Influence of Shot Peening on 70/30 Brass Residual Stresses Using Plasticity Theory

Hussain J. M. Alalkawi; Qusay Khalid Mohammed; Abbas A. AL; Asadi

Engineering and Technology Journal, 2009, Volume 27, Issue 16, Pages 3064-3075

Residual stresses play an important role in the behavior of structures
subjected to static and dynamic loads. The main aim of this study is to estimate experimentally the residual stresses in 70/30 brass material tested in bending and torsion using the plasticity theory. The influence of shot peening process on the tensile residual stresses is discussed. It is shown that the shot peening strongly influences the residual stresses, i.e. shot peening will reduce the tensile residual
stresses by 13.6% of the yield strength in bending tests. While will reduce the tensile residual stresses by 22% of shear yield stress in torsion tests.