Print ISSN: 1681-6900

Online ISSN: 2412-0758

Keywords : SiO

Study the Effects of Nano-Materials Addition on Some Mechanical Properties of Cement Mortar

F.A. Rasin; L.K. Abbas; M.J. Kadhim

Engineering and Technology Journal, 2017, Volume 35, Issue 4, Pages 348-355

This research involves nano-materials addition and interaction with cement mortar behavior for many mortar samples under variable curing time with constant water to cement ratio (W/C = 0.5). Some mechanical properties such as (compressive and flexural strength tests), durability (by water absorption test) were studied. The effect on the (Al-Mass cement) Ordinary Portland Cement (OPC) type (I) by additives with small amounts of nano-particles (SiO2) and (Al2O3) were investigated in this research. The nano materials additives were added on the mixture of mortar with the percentages (1, 2, 3, 4 and 5%) for both nano materials with constant (W/C) ratio and also the amount of the fine aggregate used three times the amount of cement. The results shows that, the strength of the mortar consist both nano materials give better properties than mortar without nano materials in all tests. But nano silica additive gives good properties up to (3%) than mortar with nano alumina additive which give proprietress up to (2%).

Study the Effect of Nano Ceramic Particles on Some Physical Properties of Acrylic Resins

Q.A. Hamad

Engineering and Technology Journal, 2017, Volume 35, Issue 2, Pages 124-129

In the present research, study the effect of adding two different types of reinforcing particles, which included: nano-alumina (nano-Al2O3) and nano-silica (nano-SiO2), that added with different volume fractions of (1%, 2% and 3%), on some physical properties of composite prosthesis complete denture base materials by using self (cold) cure poly methyl methacrylate (PMMA) resin as new fluid resin matrix. In this research, the composite prosthetic dentures specimens consist of two groups were prepared by using (Hand Lay-Up) method according to the types of reinforced particles, which includes: the first group consists of PMMA resin reinforced by nano-alumina particles, and the second group consists of PMMA resin reinforced by nano-silica particles. The physical tests were performed on these specimens include (water absorption test and thermal behaviors test). The result of this study showed the values of (thermal conductivity and thermal diffusivity) properties increased with increasing the volume fraction of both (nano-Al2O3 and nano-SiO2) particles in PMMA complete denture base materials. While, the values of (water absorption and specific heat) properties decreased. In addition, the addition of (nano-Al2O3) particles has a noticeable effect on the all properties of composite material for prosthetic denture base specimens more than the (nano-SiO2) particles.

Improving the Metal Removal Rate (MRR) in Electro Discharge Machining by Additives Powder

Saad Kariem Shather; Ruaa Amer salim

Engineering and Technology Journal, 2016, Volume 34, Issue 14, Pages 2766-2774

Electro discharge machining (EDM) is one of non-traditional machining processes which is used in important application. This paper has focused on improving material removal rate by adding powders (Al2O3 particle size 15-35m) and (SiO2 particle size 20-30m) to kerosene solution through EDM process with different ratios (0.1, 0.14, 0.18 to 0.25 g) particle size for each liter using different values of currents (8, 16 and 30 Amp) and (140 Volt) and (Toff, Ton 25 and 37 μSec),
Medium carbon steel is used as a workpeice and copper as electrode, the material removal rate (MRR). It has been found that maximum MRR was (0.2969) g/min when adding SiO2 powder (0.25)g/l and maximum MRR was (0.2781)g/min when adding Al2O3 powder (0.25)g/l, the Minitab model program was used to predict the MRR which gives a good result and agreement with experiments 99%.

Comparison Study of Erosion Wear and Hardness of GF/EP with Nano and Micro SiO2 Hydride Composites

Aseel Basim Abdul-Hussein; Fadhel Abbas Hashim; Tamara Raad Kadhim

Engineering and Technology Journal, 2015, Volume 33, Issue 9, Pages 1761-1774

The objective of this research is to study GF / EP nano and micro silicon dioxide (SiO2)composites were prepared with different volume percentage of nano and micro SiO2 powder (2,4,and 6 wt.% ). Atomic force microscopy techniques was used to measure the grain size of nano SiO2 powder (average diameter 38nm) and particle size analyzer techniques was used to measure the grain size of micro SiO2 powder (average diameter 6.069µm). Erosive wear behavior of this composite under three different impingement angles 30°, 60° and 90°and three angular silica sand abrasive particle sizes approximately 425, 600 and 850 μm and hardness (shore D) were study.In general the erosion wear of micro composites have lower resistance erosion than nanobased Materialcomposites other. Erosion resistance increase as the volume fraction increase. Nano composites of GF / EP with SiO2 have many advantages over micro composites from the view point of wear and hardness tests. The worn surface features of unfilled and filled G-E composites were examined using scanning electron microscopy (SEM) and results indicates more severe damage to matrix and glass fiber in unfilled composite system as compared to SiO2 filled composites.

Judd–Ofelt analysis of Spectroscopic properties of Nd+3:SiO2 Prepared via Sol-Gel

Mohammed. A. Hamza; Majeda A. Ameen; Hanaa M. Yaseen

Engineering and Technology Journal, 2015, Volume 33, Issue 5, Pages 848-855

Doped and undoped nano particular silicate dioxide was prepared via sol–gel method under varying conditions. The optical properties of prepared samples were investigated by a variety of techniques, including X-ray diffraction, UV- Visible spectroscopy, FTIR spectroscopy and fluorescence spectroscopy. The peak of the fluorescence spectrum was recorded at the wavelength around to 1048nm, which it is close to known fluorescence peaks of Nd:YAG crystal in NIR region. A Judd-Ofelt analysis is performed to calculate the spectroscopic properties of Nd3+ions embedded in SiO2 and compare it with spectroscopic properties of Nd:YAG crystal.The conclusions behind this study show that the doped silicate samples have a high peak emission cross-section σp , which gives an acceptable indication in the direction of using Sol-Gel technique to prepare Nd:SiO2 as a solid state laser active medium.

Investigate and Comparison Effect add Amorphous and Crystalline - Nano SiO2 on Properties of Concrete

Rami Joseph Aghajan Sldozian

Engineering and Technology Journal, 2015, Volume 33, Issue 3, Pages 547-555

In this paper, the study included the comparison between amorphous silica and crystalline silica (quartz), and with nano scale size, two types of silicawere added to concrete by ratios (5%, 10%, 15%, and 20%) as a replacement by the weight of cement. Destructive and non-destructive tests wereconducted on the specimens, the results show in destructive test the compressive and tensile strength increase in 15%wt addition ratio in both types of silica, but in amorphous silica was high than in quartz.The results of non-destructive tests show in (Schmidt Hammer) the 15% ratio in both kinds of silica show high hardness than other ratios. Ultra sonic (pules velocity) test, noted the better quality was in 15% ratio in amorphous silica and also show fastest pules velocity.