Fatigue failure is almost considered as the predominant problem affecting automotive parts under dynamic loading condition. Thus, more understanding of crack behavior during fatigue can strongly help in finding the proper mechanism to avoid the final fracture and extent the service life of components. The main goal of this paper is to study the fracture behavior of low carbon steel which is used mostly in automotive industry. For this purpose, the fractography of samples subjected to high and low stress levels in fatigue test then was evaluated and analyzed. Hardness and tensile tests were carried out to determine the properties of used steel. Also, the samples were characterized by microstructure test and XRD analysis to examine the constitute phases. The fatigue test (S-N curve) was done at stress ratio (R= -1), and the fracture examination was perform using Scanning Electron Microscope (SEM). The results of microstructure and XRD analysis were indicating that the Ferrite and a little amount of pearlite are the dominant phases of this steel. Whereas, the fractography observations reveal that the void coalescence ductile fracture is the main failure mode in samples with high stress level, while the ductile fracture (void coalescence) with Transgranular Cleavage fracture was noticed in low stress fatigue mode for this alloy.
In this research the hard chromium electroplating process, which is one of the common methods of overlay coating was used, by using chromium acid as source of chromium and sulphuric acid as catalyst since the ratio between chromic acid and sulphuric acid is (100 : 1) consequently. Plating process was made by applying current of density (40 Amp / dm2) and the range of solution temperature was (50 – 55oC) with different time periods (1-5 hr). A low carbon steel type (Ck15) was used as substrate for hard chromium electroplating. Solid carburization was carried out for hard chromium plating specimen at temperature (925oC) with time duration (2 hr) to be followed with quenching and tempering
... Show MoreThis study aimed to evaluate the effectiveness of a novel concrete-encased column (CE) using small circular steel tubes filled with cementitious grouting material (GFST) as the primary reinforcement instead of traditional steel bars. The research involved three different types of reinforcement: conventional steel bars, concrete-filled steel tubes with 30% of the reinforcement ratio of steel bars, and concrete-filled steel tubes with the same reinforcement ratio as steel bars. Twenty-four circular concrete columns were tested and categorized into six groups based on the type of reinforcement employed. Each group comprised four columns, with one subjected to concentric axial load, two subjected to eccentric axial load (with eccentrici
... Show MoreDialogue is one of the most important means of calling to the Creator, as it is one of the scientific and verbal activities carried out by a group of interlocutors to present ideas they believe in, and evidence and proofs that express their views and demonstrate the reason for their belief in them, In order to arrive at the truth or a radical solution to a specific problem, so the interlocutor should pay attention to this science, study it and its etiquette, because the purposeful dialogue requires that the funniest of them be the most knowledgeable and knowledgeable about the axis of the hadith, and the funniest must also be able to be convinced of the rule of difference of opinion that does not spoil the issue of friendly They must also c
... Show MoreThis prospective study investigates the prevalence of methicillin-resistant S.aureus (MRSA)
in burn unit of Al-Kindy Iraqi hospital, their susceptibility to antibiotics and bactericidal effect of near
infrared light from high powered 1064nm Nd: YAG laser and green light 532nm from SHG Nd: YAG laser
using various energy densities on these bacteria. Twenty four clinical isolates of S.aureus out of sixty
four examined patients with sever burn ulcers.MRSA was associated with 50% of S.aureus infections
.Results of antimicrobial susceptibility revealed that MRSA were multidrug resistant. After laser treatment
of non MRSA with Nd:YAG with wavelength of 1.064nm, 4mm beam diameter, energy density of
0.636 kh/cm2 and 180sec ex
According to the importance of the subject of research, and the importance of the surveyed organization as a dynamic sector of the country in general , The research attempts to suggest to service organizations in general reconsidering the currently adopted mechanisms in the redesign of its functions , and in the services provided industry . The data was collected from (98) Director Mangers , head of department and head of division . The research tool is the questionnaire , which included (50) items . The results show Significant Effect & Correlation relationship between the two variables due to their dimensions . These lead to he application of job enrichment technology will increase the organization's ability to possess efficient hu
... Show MoreThe purpose of this study is to investigate the histopathological response of dentinopulpal
response of human teeth to the Er: YAG laser cavity preparation in comparison with the conventional
class I cavity preparation. Thirty five sound human upper and lower first premolar teeth which were
needed to be extracted for orthodontic purposes were used in the study. Regarding to the method of
cavity preparation, the teeth were grouped into three groups; Group1; Control group which consists of
seven sound teeth without cavity preparation, Group2; Conventional cavity preparation group and group
3; Er: YAG laser cavity preparation group. Each of Group2 and3 consists of fourteen teeth that is
subdivided into: A. 7teeth that e
In The Name of Allah Most Gracious Most Merciful
It is no secret to everyone that the endowment is an important nucleus for the prosperity of Islamic civilization, especially in the fields of education, health, economy, and defensive military actions that fall within the door of jihad, and so on. Al-Ashraf, Qom Al-Quds, Cairo, and other parts of the Islamic world. What we will see in the research.
The introduction of Industry 4.0, to improve Internet of Things (IoT) standards, has sparked the creation of 5G, or highly sophisticated wireless networks. There are several barriers standing in the way of 5G green communication systems satisfying the expectations for faster networks, more user capacity, lower resource consumption, and cost‐effectiveness. 5G standards implementation would speed up data transmission and increase the reliability of connected devices for Industry 4.0 applications. The demand for intelligent healthcare systems has increased globally as a result of the introduction of the novel COVID‐19. Designing 5G communication systems presents research problems such as optimizing
This study aims to impact statement played by banking governance according to the decisions of the Basel Committee in achieving the strategic objectives of the banks, But order to achieve the this goal has been the adoption of two hypotheses in addition to the two main hypotheses as sub answered preliminary The study seeks to verify their health and two (no correlation relationship and impact between Banking governance and achieve strategic objectives), has been tested hypotheses. Study has reached
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