Print ISSN: 1681-6900

Online ISSN: 2412-0758

Keywords : SPSS software


Studying and Modeling the Effects of Quartz Addition and Heat Treatment on Mechanical Properties of Glass-Ceramic Coating

Ali H. Ataiwi; Ibtihal A. Mahmood; Jabbar H. mohmmed

Engineering and Technology Journal, 2014, Volume 32, Issue 7, Pages 1811-1824

In this work, a new glass-ceramic coating has been developed and applied, as a single coat without prior chemical treatment of the surface, using the dipping technique on metal substrate. the coating are designed for application on varies grades of low alloy steel, the selected substrate was low carbon low alloyed steel with (0.2)%C. Various heat treatments at temperatures ( 500,550, and 600˚C ) at different times (60 & 120)min and with quartz addition in the range (0-15)% were used to obtain a glass-ceramics that have the optimum coating properties. These coating have been characterized by x-ray diffraction analyses and the results showed presence of a number of microcrystalline phases which are formed during the heat treatments. The results showed the suitability of this coating for protection the metal substrate which was used in present work. The results of tests also indicated that the mechanical properties ( hardness, adhesion strength, and thermal stability) of resultant coating were greatly improved by both addition of quartz into enamel frit and heat treatments for all cases, this is attributed to the formation of complex network from crystalline phases(Li2SiO3, Li2TiSiO5, NaAlSi2O6, and SiO2) which are the main phases in the resultant glass-ceramic coating. It has been found that the heat treatment at 600˚C for 120min with 15% quartz addition brought the optimum values for ( hardness, adhesion strength, and thermal stability) of resultant coating which are improved by (70.58%, 33.84%, and 39.68%) respectively. Mathematical modeling is implemented and regression equations are obtained using ( SPSS ) software to predict the experimental data for mechanical properties of resultant coating. Comparing the predicted and measured values gives high prediction accuracy. The accuracy of prediction has been (98%, 98.5%, and 97.4%) for ( hardness, adhesion strength, and thermal stability) respectively.

Wear Resistance of a New Glass Ceramic Coating

Jabbar H. mohmmed; Ibtihal A. Mahmood; Ali H. Ataiwi

Engineering and Technology Journal, 2014, Volume 32, Issue 6, Pages 1472-1484

A new wear resistance glass-ceramic coating system iron (low alloyed low carbon steel) based substrate was developed. The effects of heat treatment conditions and mill additions on wear resistance of developed coatings resistance were studied. The coating materials showed excellent properties for protection the iron substrate from wear. Also, in this work mathematical modeling is implemented and regression equations are obtained by using ( SPSS ) software to predict the experimental data for wear rate. Comparing the predicted and measured values gives high prediction accuracy.

Modeling of The Corrosion Behavior of Enamel Coatings in Different Aggressive Media

Ibtihal A. Mahmood; Jabbar H. mohmmed; a A. Khalaf; Bayda

Engineering and Technology Journal, 2014, Volume 32, Issue 6, Pages 1530-1543

In this study an attempt has been made to formulate materials for glass ceramic enamel coating that can be applied directly onto cast iron substrate for corrosion control. Different 'proportions(4.95) %wt. to form four batches. The batches were mixed with water to form slips which were used to coat already prepared cast iron surfaces and were allowed to dry in the oven. The coated cast iron plates were fired at temperatures of 850˚C to mature and factually heat treated at 680˚C.
The coatings were observed and also chemical tests were conducted to determine the corrosion properties of the resultant coatings. The chemical tests were evaluated using a suitable standard methods and special attention was paid to the type of aggressive solution, and temperature.
The results show that the coatings matured and adhered very well to the sub strateand showed good corrosion resistance in H2SO4,HCl,C6H8O7, H3PO4, and NaOH solutions. The results indicated that the corrosion rate in both acid and alkali media was increased strongly with the increasing temperature.The coatings prepared with the zircon showed better results in terms of acidcorrosion resistance than those prepared with the other crystalline agents. However, the corrosion rate of the zircon containing coating in sulfuric acid was higher than that in hydrochloric acid. Also, it is found that there is absolutely no weight loss for any of the four types of the coating in neither citric nor phosphoric acids. At the same time, the results for alkali corrosion resistance indicate that the act of the four series is very similar to each other, for the four coatings there is no high corrosion rate until the temperature exceed 100˚C after that the rate increases in a very quick manner. From the results it is found that the enamel with lithium oxide was not affected by the alkali solution at all, this behavior is associated with the presence of crystalline β-Spodumene, and β-Eucryptite, which have an extremely high corrosion resistance especially for alkali medium. Mathematical modeling is implemented and regression equations are obtained by using (SPSS) software to predict the experimental data for acid and alkali corrosion rate. Comparing the predicted and measured values gives high prediction accuracy.

Prediction of Metal Removal Rate and Surface Roughness in Electrochemical Machining (ECM)

Saad kariem Shather; Hiba Husien Alwan

Engineering and Technology Journal, 2012, Volume 30, Issue 8, Pages 1415-1427

Electrochemical Machining (ECM) is a relatively important method of removing
metal by anodic dissolution. In this research the ECM was used to remove the metals
from the internal hole of the workpiece.The tool used was made from brass. This
research focuses on the parameters of the change in gap size, the change in current
density, and the change of the tool roughness on the Material Removal Rate (MRR),
and Surface Roughness of the workpiece. The Statistical Package for Social Science
(SPSS) software was used to predict the results. It was found that for the surface
roughness the coefficient of determination of the prediction was (0.982) and the
accuracy of prediction (97.15%). For the Material Removal Rate in (g/sec) units the
coefficient of determination of predicts was (0.991) with accuracy of prediction
(98.29%).

Studying and Modeling The Effects of Quartz Addition and Heat Treatment on Corrosion Properties of Ceramic Coating

Ali H. Ataiwi; Ibtihal A. Mahmood; Jabbar H. mohmmed

Engineering and Technology Journal, 2011, Volume 29, Issue 12, Pages 2564-2579

In this work, a new glass-ceramic coating has been developed and applied, as a single coat without prior chemical treatment of the surface, by using the dipping technique on metal substrate. the coating are designed for application on varies grades of low alloy steel, the selected substrate was low carbon low alloyed steel with (0.2)%C. Various heat treatments at temperatures ( 500,550, and 600˚C ) at different times (60 & 120)min and with quartz addition in the range (0-15)% were used to obtain a glass-ceramics that have the optimum coating properties. These coating have been characterized by x-ray diffraction analyses and the results showed presence of a number of microcrystalline phases which are formed during the heat treatments. The results of corrosion resistance tests indicated that the acid resistance was greatly improved by addition of quartz into enamel frit but at same times decreased the alkali corrosion resistance, while the heat treatments improved both acid and alkali resistance for all cases, this is attributed to the formation of complex network from crystalline phases. The results also indicated that the heat treatment at 600˚C for 120min with 15% quartz addition brought the optimum values for acid resistance property which are improved by 86.66%, while the optimum values for alkali resistance property was brought with free quartz added samples which were treated at 600˚C for 120min. Mathematical modeling is implemented and regression equations are obtained by using ( SPSS ) software to predict the experimental data for acid and alkali corrosion rate. Comparing the predicted and measured values gives high prediction accuracy. The accuracy of prediction has been (82.58%, and 96.7%) for acid and alkali resistance properties respectively.