Print ISSN: 1681-6900

Online ISSN: 2412-0758

Keywords : Corrosion behavior


Effect of Adding TiO2on Some Mechanical Properties of Galloy

Osamah A. Khadhair; Rana A. Anaee; Kadhum M. Shabeeb

Engineering and Technology Journal, 2021, Volume 39, Issue 5A, Pages 695-702
DOI: 10.30684/etj.v39i5A.1395

Because of importance the Ga alloys in dental applications, many attempts were  done  to  improve  the  properties  of  this  alloy. The  currentwork involves  addition  of  TiO2nanotube  powder  to  Galloy  to  improve  somemechanical  properties.  These  properties  included  hardness,  compression, and creep. The characterization of prepared TiO2/Galloys with five wt% of TiO2(1, 2, 3, 4, and 5 wt%) was done by XRD and SEM/EDS. The results showed  that  the  hardness,  compression, were  increased  with  increasing percentage  of  added  TiO2,  while  creep  decrease.Some phases  such as β-Sn,  Ag2Ga  and  Ag9In4were  contributed  to  improve  the  properties  of  new TiO2/Galloycomposites.

Investigation of Corrosion Behavior for Copper-Based Shape Memory Alloys in different Media

E.S. Al-Hassani; A.H. Ali; S.T. Hatem

Engineering and Technology Journal, 2017, Volume 35, Issue 6, Pages 578-586
DOI: 10.30684/etj.35.6A.4

Copper based shape memory materials was interesting group of metal alloys that have a widespread potential in medical and industrial application due to their characteristics ,the possibility of exhibiting shape memory behavior and lower cost. In this research the alloy (Cu-(15-40) wt%Zn-6wt.%Al) has been prepared by powder metallurgy technique Zn element (15, 20, 25, 30, 35, 40 wt%Zn) and fixed percentage of Al content which is 6.wt%Al then aluminum replaced by (Si, Sn, Ni )element at fixed percentage of 6wt.%, in order to study the effect of these elements on SMA. After samples preparation examination were done by using XRD, SEM technique, DSC, Vickers hardness, Archimedes method to measure the porosity percentage and corrosion rate in different solutions (HCl, NaOH and SEAWATER).The XRD and microstructure results show that all samples with and without additives consist of two phases (β-phase) and (α-phase) at room temperature and the addition of alloying elements in these percentages does not have effect on present phases. the hardness increased with zinc content because the formation of intermetallic compound of CuZn that responsible to hardness while The addition of Si ,Sn and Ni leads to lower the hardness than aluminum. The bulk density increased with the alloys without addition alloying elements(Si, Ni and Sn ) while apparent porosity decreased with it the reason for this phenomenon due to the characterization of alloying elements that addition to the alloy. From the results of corrosion test can be show the alloy with 35wt% Zn have the higher corrosion resistance in all media (HCl, NaOH and sea water) and the addition of alloying element lead to improve the corrosion resistance. Finally, it is observed that the Copper base shape memory alloys with these types of additives are suitable for use in different application.

Preparation and Characterization of Biomedical Ni-Co-Al Shape Memory Alloys

Emad S. Al-Hassani; Sahib M. Al-Saffar; Zena Abdul Ameer

Engineering and Technology Journal, 2016, Volume 34, Issue 7, Pages 1457-1472
DOI: 10.30684/etj.34.7A.17

This research presents microstructural characterization of the CoNi Al shape memory alloy with focus on understanding the significant properties as well as the relation between the physical properties and microstructure of this alloy. Melting technique were used to prepare Co Al Ni shape memory alloys, where scanning electron microscope, light optical microscopy and x-ray diffraction investigations showed that structure of this alloy is polycrystalline double phase (β and γ) structure, and it found that the grain size and phase fraction of β phase was ranged from 9 to 16 μm and (50-80) % respectively. It was found that by increasing the heat treatment time the phase fraction of hard β phase increased and phase fraction of ductile γ phase decreased, and consequently the grain size and the hardness of β phase increased. Differential Scanning Calorimeter results showed that transformation temperature decreased by increasing Al/Co, that Co content affected on transformation temperature. Tafel Curves showed the corrosion behavior in simulation body fluid, where the corrosion rate was ranged from 0.13 to 0.47 mpy and increased with each of increasing the annealing time and Co content, and from cyclic curves, the pitting corrosion possibility is not observed due to the formation of a protective layerthat formed by Al element.According to these properties and behavior, it was found that this alloy could be a good choice to be used for biomedical applications, especially in surgical, catheter tools and medical instruments.

Corrosion Behavior of V2AlC and Cr2AlC Materials in Acidic Media

Rana Afif Majed; Ahmad Mohammed Hasan; Russul Fadhel Faleh

Engineering and Technology Journal, 2015, Volume 33, Issue A4, Pages 845-854
DOI: 10.30684/etj.33.4A.8

This work involves the manufacturing of MAX phase materials including V2AlC and Cr2AlC using powder metallurgy as a new class of materials which characterized by regular crystals in lattice. Corrosion behavior of these materials was investigated by Potentiostat to estimate corrosion resistance and compared with the most resistant material represented by SS 316L. The experiments were carried out in 0.01N of HCl and 0.01N H2SO4 at four temperatures in the range of 303-333K. Polarization resistance values which calculated by Stern-Geary equation indicate that the MAX phase materials have more resistance than SS 316L. Optical microscopy results for corroded surfaces were confirming the resistivity of MAX phase materials.

The Effect of Iron Addition on the Dry Sliding Wear and Corrosion Behavior of Cu Al Ni Shape Memory Alloy

Abdul Raheem . K. Abid Ali; Zuheir T. Khulief.Al-Tai

Engineering and Technology Journal, 2010, Volume 28, Issue 24, Pages 6888-6902

In this paper, dry sliding wear and corrosion behavior of Cu + 13wt% Al + 3.8 wt% Ni was prepared by powder metallurgy. Dry sliding wear has been studied based on pin on disk at constant velocity and constant sliding distance .Corrosion behavior in 5 wt% NaOH solution based up on potentiostatic ( Tafel ) has been presented for base shape memory alloy ( Cu + 13% Al + 3.8 % Ni ) in two cases austenitic and martensitic phase state . Further more , the effect of Fe additions as ( 0.4 , 0.8 and 1.2 wt% ) on the sliding wear and corrosion behavior of
base alloy has also been studied .It is clear that Cu Al Ni shape memory alloy in martensitic state has more wear resistance than in austenitic structure . Also , corrosion resistances are better than in martensitic structure because the alloy has corrosion current density as 336.45 μA/cm2 in martansitic where as the corrosion current density is 633.62 μA/cm2 in austenitic structure . Further more , when the
iron content increases , wear and corrosion rate increase too .