Print ISSN: 1681-6900

Online ISSN: 2412-0758

Keywords : corrosion resistance

A Desirability Function for Evaluation of Corrosion Behavior for Nanocoated- Steel Using Electroless Technique

Muroog M. Shinyar; Abbas Kh. Hussein; Laith K. Abbas

Engineering and Technology Journal, 2021, Volume 39, Issue 6, Pages 946-955
DOI: 10.30684/etj.v39i6.2009

The current work is conducting an experimental investigation into the effect of those technical parameters, called nanomaterial, bath temperature and plating time on the micro-hardness and corrosion rate of electroless plated low carbon steel undergoing electroless deposition operation. It was used to prepare (Ni-P/ Nano TiO2), (Ni-P/ Nano Al2O3) and (Ni -P/ Nano SiO2) alloys in this research. The Taguchi design is used to describe the variations located within the corrosion and mechanical properties. To achieve a comprehensive study, a Taguchi-based design was used to account for all applicable combinations of factors. Experimental models had been advanced that linking the response and method parameters to the results of those experiments. Validation of these models is done using analysis of variance (ANOVA). The desirability function is used to simultaneously optimize all the response. Finally, the optimum combination of method parameters resulting (bath temperature=90 oC, plating time =120 min.  and Nanomaterial=(Al2O3)), nanomaterial was observed to be the major process parameter on the responses of the electroless-plated low carbon steel with an impact ratio of (47%) based on the (ANOVA) results. 

Effect of Applied of Pre-Stresses on Corrosion Behavior of 304 Stainless Steel in 1N H2SO4

Sami Ibrahim Jafar; Israa Abud Alkadir; Samah Abdul Kareem Khashin

Engineering and Technology Journal, 2016, Volume 34, Issue 3, Pages 600-612

This research is devoted to study the effect of applying different pre-tensile stresses (255,305,355,405,455,505 555 and 605) MPa on the microstructure, hardness and corrosion behavior of 304 stainless steel in 1N H2SO4. The stress-strain curve was drawn for standard (304) stainless steel in laboratory environment. The curve was divided into three zones. At zone one the values of elastic pre-stresses vary between (σ0 - σpro.) MPa. The results showed; that the corrosion rate was very little increased compared with that of as received (304) stainless steel. The microstructure presented undeformed austenitic grains and the hardness value was (157.433) Hv. At zone two the value of plastic pre-stress varies between (σpro.- σ U.T.S) MPa. The corrosion rate increases after applying pre-stress between (σ255 - σ 455) MPa. The microstructure showed that the austenitic grains begin to deform in the direction of applied pre-stresses. The maximum hardness at this region was (229.2) Hv, but at higher pre-stress (σ455 – σ 605) MPa, the corrosion rate decreases. The microstructure inspection shows the deformed austenitic grain and ά-martensitic phase needle are appeared inside austenitic grains and the hardness reached the maximum value (332.433) Hv. At zone three the values of pre-stresses are between (σ605 - σf) MPa. The results showed that the corrosion rate increases. The investigation of microstructure showed that there are distortion in austenitic grains and ά- martensite phase observed inside austenitic grains. The hardness reached the maximum value at (354.3) Hv. The necking of gauge length of specimens occurs in specimens and this leads to deterioration in original properties

Corrosion Resistance of Aluminum Alloy 7020-T6 in Sea Water

Mustafa Khaleel Ismael

Engineering and Technology Journal, 2011, Volume 29, Issue 8, Pages 1482-1490

The present work is aimed to investigate the effect of heat treatment on corrosion resistance of Al-alloy 7020-T6 in sea water, the specimens which manufactured by (1.5*1.5*0.2) cm, according to ASTM (G31-72) [1] The heat treatment was carried out at 480°C and water quench after that artificial aging are implemented at temperature 150°C for (1, 4) hours. Microstructure and phase properties after heat treatment and corrosion test were investigated by optical microscope; X-ray diffraction and
computer potentiodynamic polarization technique have been used to study corrosion behavior in 3.5% NaCl. The results of corrosion resistance 7020-T6 decrease by solution heat treatment and, increase the holding time from 1- 4 hour would increase the corrosion rate, Intermetallics compounds containing zinc represent as the sacrificial anode and control pitting corrosion in 7020-T6 alloy also, the artificial
ageing time increase the precipitation of zinc and decrease pitting corrosion at 1 hour.

One Parameter Composite Semigroups of Linear Bounded Operators in Strong Operator Topology of Schatten Class Cp

Samir Kasim Hassan; Al-Taie M; Al-Malki Anam; Al-Attar Abeer; Mustafa Khaleel Ismael; Fatema Ahmed Sadeq; Radhi A .Zboon; Jehad R.Kider; Samir K .Hassan; Hussain J. M. Alalkawi; Raad H. Majid; Rawaa A. Alomairy; Luma Abdul Ghani Zghair; Hadia Kadhim J.Al-Ogili; Assifa M. Mohamad; Abbas Sheyaa Alwan; Haider L. Aneed; Assim H Yousif; Salema Sultan Salman; Abbas Hussien Miry; Abduladhem A.Ali; Mohammed Zeki Al-Faiz; Sabah N. mahmood; Khansaa Dawood Selman; Shaymaa Tareq Kadhim

Engineering and Technology Journal, 2011, Volume 29, Issue 8, Pages 1463-1470

For semigroups of linear bounded operators on Hilbert spaces, the problem of
being in Cp , 0 Keywords