Engineering and Technology Journal

Hydrogen embrittlement is a diffusible Hydrogen that is harmful to the toughness of iron. It follows, therefore, that the harmful influence of diffusible Hydrogen can be mitigated by preventing its entry into steel. This approach was achieved by using three coating layers as a coating nanostructure thin layer by DC
sputtering on steel structural (AISI l018) and hydrogen charging (HC) effect on
uncoated and different Nano coated tensile specimens. The first layer was
Titanium as a bonding layer, the second layer was TiO2 with Al2O3, and the third
layer was Al2O3. Using a titanium Nano layer coating on AISI1018 steel tensile
specimens increased the tensile strength from 570 to 659 MPa with 16 hours of
charging, which is considered a good increase. In contrast, the elongation
remained in a steady-state with little difference in values compared to changing
the charging time and the coating of the double layer. Furthermore, it was found
that samples coated with TiO2 and Al2O3 by the DC method had advanced
hydrogen embrittlement resistance and increased tensile strength (from 565 to
680 MPa with 8 hours of charging process). Moreover, the maximum adhesion
value was related to the triple layer at 596 psi, and the lowest value was 309 psi
using the titanium layer alone. The coating time was 5 hours of the sputtering
process for all specimens. The coating layers are considered a good barrier for
hydrogen permeation through steel structures (AISI 1018).

The main contribution of this paper is to develop an innovative algorithm to accurately detect and identify the shape and color of objects under various light intensities and find their location to be manipulated by a pick-and-place robotic arm. Workpieces of various shapes and colors are dispersed on the robot's work plane and manipulated according to its specifications. The proposed algorithm utilizes the HSV color model to distinguish between different object colors and shapes. The S channel is used to detect the shapes of objects. After that, a series of filters (Median, Bilateral, and Gaussian) are applied to reduce the noise of the segmented image to make the process of discovering the shape and coordinates of the objects successful. The draw-contour method is used to discover the object’s shapes. After the shape of the object is discovered, the centroid coordinates are calculated. After extensive testing on 354 images that are captured in various lighting conditions in the range of (5-7000 lux), the overall system performance of 93.83% is achieved, and the average execution time is 2.21s. Finally, we had a dependable flexible automatic pick and place system that could correctly detect and identify the objects based on their features.

Brazing fillers for joining applications are essential to advanced material design and fabrication. Several types of brazing fillers have been developed in recent decades to join similar or different engineering materials. Important parts of automotive and aircraft components, including steel, are often joined by brazing. In this study, Similar samples of martensitic stainless steel were welded by the brazing method, using effective silver-based metal alloys. The brazing welding is done in inert gas atmosphere furnaces, by placing the samples in a special container filled with argon gas during the welding period and at a flow rate (10 to 15 minutes) inside a cylindrical furnace. Three types of metal alloys (silver, copper, and titanium) with different weight ratios of Ag, Cu, and Ti were used with a fixed welding time (10 minutes) at an appropriate temperature for each joint. A set of examinations and tests were conducted to find out the microscopic structure of the bonding site and the extent of the binder overlapping with the base material. Optical microscopy was used to study the microstructure of the weld joint. Optical and scanning electron microscopy (SEM) is used to study the joint microstructure. All joints of samples exhibited continuous bonding between the base metal and the filler metal, good wetting between the surfaces, and it was also noticed that the higher the proportion of titanium, the better the wetting between the surfaces., the greater the percentage of diffusion of the filler elements and the strength of the bonding with the base metal. The use of titanium-containing fillers in brazing is good for bonding in turbine blades of martensitic steel.

Zr2AC MAX phases are ternary carbide family with layered structures combining of the outstanding characteristics of metals and ceramics. This review study provides an overview of Zr2AC MAX phase formation mechanisms, applications, and the correlation between Zr2AC MAX phase formation mechanisms and performance in applications such solar coatings, oxidation resistance, high temperature applications, and nuclear applications. Zr2InC MAX phase has low friction and wear materials that can be used for variety applications for significant technology such as electrical spinning connections and rotating bearings. More examples, the Zr2SnC MAX phase uses for self-healing of cracks and oxidation resistance. The Zr2PbC MAX phases are elastic and electrically anisotropic in nature and appropriate for high temperature applications, optoelectronic devices, and coating materials. Studying the optical characteristics of the Zr2SeC has shown its potential for application as a shielding material in order to decrease the heating of solar. The Zr2SC is suitable for use in high-temperature technologies, such as thermal barrier coating material TBC. The Zr2AlC phase is the most attractive among all non-synthesizable ternary MAX phases, particularly for the nuclear industry. There are a lot of challenges during fabrication of the MAX phase, including synthesis temperature, the MAX phase purity, and the secondary phase (impurities). In harsh external conditions, the defect density has a substantial impact on the MAX phase's stability and thus, the methods of defect formation and migration have a considerable impact on the phases' radiation resistance and self-healing capabilities

The main challenge facing industrial companies is how to stay competitive in a fast changing world. They should adopt an effective supply chain that enables them to deliver products in a short period of time. This forced organization to change their pattern of processing and become lean. Lean manufacturing system is the best philosophy to achieve the objectives of the industrial organizations and to reduce the waste activities. The unnecessary movement, defective, waiting, inadequate processing, unnecessary inventory, excessive transport, overproduction, and the underutilization of people and facilities are the most types of waste found in the industries. Many industries have experienced the benefits of applying the lean concept in their area to improve the production processes, resources utilization, reduce production lead time, and eliminate wastes in the activities which is the goal of lean concept in the manufacturing industry. In this research, the lean concepts are presented in the leather shoes manufacturing industry in the city of Baghdad, it aimed to decrease the lead time of production, minimize the non-value time, and improve the production line. By using the most essential lean tool, value stream mapping, where the current and future map capture the flow of material and information of the production line before and after the implementation of the proposed improvement. The hybrid push/pull strategies and Kanban production were implemented to improve the production line. After adopting the suggested improvement, the production lead time reduced from 130.6 to 14.8 hours and the non-value added reduced from 118 to 10.8 minutes.

In this study, a novel bioceramic material with improved mechanical properties was prepared to be consentient with the mechanical requirements of living bodies. Cordierite was synthesized via the sintering method at 1400°C, based on a composition of 51.4% silica, 34.8% of alumina, and 13.8% magnesia. The composition of precursor materials was studied using wet chemical analysis. Three different compositions of the cordierite (30, 40, and 50 wt.%) were incorporated in hydroxyapatite and then sintered at 700, 900, and 1100°C. To visualize the characteristics of all prepared materials, scanning electron microscopy (SEM) and X-ray diffraction (XRD) were analyzed. The crystallite size was determined from XRD patterns using the Scherrer equation. Microhardness was investigated using (a digital micro hardness tester), while the compressive strength was tested using a microcomputer-controlled electronic universal testing machine (WDW-5E). The modulus of elasticity was determined from the stress-strain curve. As a result, all samples which contain cordierite powder have considerable mechanical properties as compared to the control sample. The incorporation of cordierite caused a slight increase in grain size at all sintering temperatures. Among all ratios, the second mixture, which includes 40% cordierite showed the best mechanical properties at all sintering temperatures. The percentage of 40% cordierite led to increasing the compressive strength of HA by 126.27% at 700°C, 61.52% at 900°C, and 123.05% at 1100 °C. On the other hand, the effect of this cordierite level on hardness increased by 94.04% at 700°C, 141.29% at 900°C, and 128.44% at 1100°C. The values of elasticity modulus ranged between 15-37 GPa, i.e. consistent with that of cortical bone.

Numerical analyses offer a cost-effective and efficient alternative to experimental investigations, and Finite Element (FE) models have become a popular tool to simulate the behavior of Fiber metal laminates (FMLs) under impact loads. This study verified the reliability of the proposed FE models to predict the perforation response of the FMLs investigated under low-velocity impact loadings. The validation of the FE models was assessed through comparison with the corresponding results of the experimental work. The results showed that the proposed simulations are capable of predicting the dynamic response of the laminates investigated with a high degree of success. The parametric studies were conducted on 2/1 titanium FMLs based on 2-ply composite cores and 2/1 aluminum FMLs based on 4-ply composite cores under impact with a variety of loading conditions. The developed FE models were then used to explore the structural behavior of the fiber metal laminates investigated with an extended variation of parameters, i.e., projectile striking angle, impact locations, t geometry of the projectile, and velocity. The results of the FE models
are presented in terms of load-displacement traces, energy absorption, and failure
modes. The findings of this study contribute to the understanding of the
structural behavior of FMLs under impact loads and can inform the design and
optimization of FMLs for various engineering applications. The use of FE
models provides a cost-effective and efficient means of exploring the structural
behavior of FMLs under different impact conditions, which can reduce the need
for costly and time-consuming experimental investigations.

The corporation of rare earth metals (lanthanides series) with other metals gives good properties in different fields, such as protecting the metallic surface from corrosion risk. In this work, the investigation on adding gadolinium (Gd) and samarium (Sm) as rare metals to bio-inert titanium (Ti) as transition metal was done to protect stainless steel (SS 316L) as bio metallic implant which is used in biofield because of its excellent mechanical properties, low costs, biocompatibility, inertness, and mechanical properties, chemical stability, workability, and high corrosion resistance. The corporation was done through coating using direct current (DC) sputtering technique from the target of these metals mixture to measure some properties. The surface characterization by X-ray diffraction (XRD) gave many phases represented by different GdxNiy in addition to the Ni3Ti phase and Ni5Sm phase. The scanning electron microscopy and energy dispersive X-ray spectroscopy (SEM/EDS) results showed the distribution of coating metals as a dense thin film with a good ratio of coating metals; this dense film gave lower surface roughness as illustrated through Atomic force microscopy (AFM) examination from 25.20 nm for the uncoated sample to 15.12 nm for the coated sample with a reduction in the hardness from 187 HV for the uncoated sample to 119 HV for the coated sample as well as increasing contact angle test (wettability) from 90° for base stainless steel surface to 117.723° for coated surface, these results enhanced the compatibility with giving good resistance from corrosion test, with achieving protection efficiency equal to 99.02%.

Using bioactive and biocompatible coatings to biofunctionalized metallic implant surfaces for enhanced bone regeneration while resisting bacterial infection has attracted materials scientists' interest. Bio-metallic Ti-25Zr disc sample was prepared using powder metallurgy and then coated using an electrospinning method to form a nanocomposite fiber as a coating layer over the surface of the metal alloy substrate. Three nano-compounds (Nano-hydroxyapatite, Nano-Titanium dioxide, Nano-strontium titanite) were added individually to the Polycaprolactone/Chitosan blend to prepare the electrospinning solutions. The results show a significant improvement in biocompatibility for the coated samples after seven days of (MC3T3-E1) cell culture. Cell viability percentages were significantly higher for the coated samples compared to uncoated ones, with values of PCL/Chitosan/nHA (HA1) has 239.45±17.95%, PCL/Chitosan/nSrTiO3 (SR1) has170.09±8.12%, and PCL/Chitosan/nTiO2 (TI1) has 117.19±19.42%, while bare Ti-25Zr has 80.52±1.97%. Cell proliferation also shows a remarkable increase with time for coated samples, and the enhancement reaches 197.76% for (HA1), 111.38% (SR1), and 45.81 % (TI1) in comparison with (bare Ti-25Zr). For the antibacterial test, no inhibition zone for the control sample (bare Ti-25Zr) was observed, while the coated samples showed a suitable and comparable inhibition zone. The coating procedure is simple and inexpensive, and composite nano-fiber has high biocompatibility and promise in orthodontic and orthopedic bone regeneration.

The pack cementation process was used to create a type of Y2O3+ZrO2 doped Cr-Co-modified aluminide coating that takes advantage of the synergistic effects of nano Y2O3 and ZrO2 particles. A Ni-based superalloy (type IN625 type) was coated with pack powder containing: Al as a source of aluminum; Cr as a source of chromium, Co as a source of cobalt, NH4Cl as a source of activator; nano Y2O3-ZrO2 as a source of reactive element oxide; and Al2O3 as a source of filler metal. The process was carried out for 6 hours at 1100oC temperature. The microstructure characterization of the coating was performed by SEM, EDS, and XRD. It was found that the cross-section of the coating obtained was uniform and free from cracking. The maximum hardness value was found at the outer layer (997H.V.) and decreased toward the core sample core (366H.V.). The coating's microstructure consists of an outer layer, a transition layer, and an IDZ. The average coating thickness is 132.37, 36.11, and 37.65μm for the outer layer, transition layer, and IDZ, respectively. The XRD analysis of the coating system after 6 hours at 1100oC revealed phases formed by AlNi3, CoO, Al-Cr-Co, and Cr4NiZr. The n (growth rate time constant) and Kp (parabolic rate constant) values increase with increased oxidation temperature. It was found that adding Zr and Y to the Cr-Co-modified aluminide coating might increase the oxidation resistance.

Due to their excellent mechanical and biocompatibility characteristics, CoCr-based alloys are frequently employed in orthopaedic implant applications. It is necessary to maximize their general characteristics, corrosion resistance, and ion release. Despite several benefits, coating with torch flame spray has weaker adherence. As a result, powder metallurgy was employed to combine Si and Nb elements with CoCr alloys. CoCrNb and CoCrSi alloys were sprayed with multiple torch flames to apply two different kinds of Nano-coatings (A: 75% HAP+ 25% SiC, and B: 75% Zeolite+ 25% ZrO2). In two samples, alloying elements Nb and Si were added at a concentration of 5 wt.%. Various characterization methods are employed, such as field emission scanning electron microscopy (FESEM) or energy dispersive X-ray spectroscopy (EDS), an ion release test, atomic absorption spectroscopy (AAS), a wear test, corrosion measurement, atomic force microscopy (AFM), and an adhesion strength test. According to the results, coating (type A) and (type B) increase the wear resistance of CoCr alloy. The zeolite+ZrO2 (type B) and HAP+SiC (type A) coating layers act as barriers to the release of Co and Cr ions from CoCr alloys. There were varying degrees of roughness in the coated samples, which resulted in corrosion pitting. According to tensile pull-out tests, the two-torch flame spraying technique provided a stronger bond with the substrate than the single-torch flame spraying technique. In general, CoCrSi coated type B are the best to be implanted where the cytotoxicity is 0% in the human body, thus an excellent biocompatibility.