Mechanical and corrosion resistant properties of ATIG welded 2205 duplex stainless-steel via different fluxes

Hussein Alrobei,Kamel Touileb,Rachid Djoudjou,Abousoufiane Ouis,Abdeljlil Chihaoui Hedhibi,Ibrahim AlBaijan,Rizwan Ahmed Malik,El-Sayed M. Sherif 대한기계학회 2021 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.35 No.12

In this study, 6 mm thick duplex stainless-steel grade 2205 plate was welded by active tungsten inert gas (ATIG) using different oxide fluxes and the effect of optimal oxide fluxes on structure, mechanical and corrosion properties was systematically analyzed and discussed. Initially, fourteen oxides were tested (SiO 2 , TiO 2 , ZnO, MnO 2 , Cr 2 O 3 , Fe 2 O 3 , ZrO 2 , SrO, CaO, MoO 3 , V 2 O 5 , Mn 2 O 3 , Co 2 O 3 and MgO). Among these, three candidate oxides, i.e., SiO 2 , Ti 2 O and ZnO were selected for further evaluation based on the depth ratio, depth-to-width (D/W), and ultimate tensile strength (UTS) results. By using Minitab 17 software, optimal combinations of these fluxes for maximum penetrations were estimated. The obtained results revealed that the optimal flux composition is 76 % SiO 2 -24 % ZnO. The results showed that the depth attained by the optimized flux is 2.9 times greater than tungsten inert gas (TIG) weld. The D/W ratio was also improved 3.7 times when contrasted with typical TIG welding. The energy absorbed in fusion zone in the case of ATIG weld is greater when contrasted with TIG weld. It was found that the weld bead obtained with optimal flux combination in ATIG weld can better withstand sudden loads. The obtained UTS value (810 MPa) for ATIG weld was close to parent metal (825 MPa) and greater than the weld produced by TIG welding (766 MPa). However, the corrosion resistant property was found to be slightly decreased for metal welded with ATIG as compared to metal welded by using TIG. These results give a comprehensive guideline for further investigations on TIG welding of 2205 duplex stainless-steel.

Effects of gating design on structural and mechanical properties of high manganese steel by optimizing casting process parameters

Hussein Alrobei,Rizwan Ahmed Malik,Abid Hussain,Meshal Alzaid,Lamia Ben Farhat,Irfan Anjum Badruddin 대한기계학회 2022 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.36 No.8

The impacts of gating design and riser system on structure-property relationship of high manganese steel specimens produced by CO 2 sand molding process were systematically examined. The designing of gating and riser system was done first using the traditional manual method and then by SolidCast simulation method. Confirmatory experiments were done to validate the obtained results. Castings were produced using both designs to verify the extent of defects. Their microstructural and mechanical properties were explored. Visual examination of castings designed by manual method showed major shrinkage defects, whereas software designed castings were quite sound showing no shrinkage (macro porosity) and micro porosity. Furthermore, optical microscopy and SEM analysis were performed to study microstructure of the specimens. It was found that the defect-free, software-designed castings with optimized parameters showed ~25 % improvement in yield strength, ~20 % in tensile strength and ~30 % in hardness.

Mechanical properties of natural screw pine fiber reinforced polyester nanocomposites

Hussein Alrobei 대한기계학회 2021 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.35 No.5

In automobile and aerospace applications, composite materials play a vital role due to their weight reduction and competitive cost. Fiber reinforced polymer (FRP) nanocomposites are suitable for such applications. Screw pine fiber is another more advanced and promising natural fiber used in the form of discontinuous fibers as reinforcement material. Three different volumetric proportions - 3 mm, 6 mm and 9 mm - of screw pine reinforced polyester composite are studied. The most economical hand-lay method is utilized to fabricate the screw pine FRP nanocomposites. The aim of production is to enhance toughness, dimensional stability, stiffness and strength by embedding particles such as fibers in a matrix. The mechanical properties are analyzed for 10 %, 20 %, 30 % and 40 % of fiber loading with various fiber lengths 3 mm, 6 mm and 9 mm. Nanofiber content of 30 % with 9 mm displayed maximum strength of impact, flexural strength, tensile strength and strong elasticity module.

Design and manufacturing of lanthanum phosphate (LaPO4)-based crucible for high temperature applications

Hussein Alrobei,Azeem Hafiz,Rizwan Ahmed Malik 한양대학교 세라믹연구소 2021 Journal of Ceramic Processing Research Vol.22 No.5

This paper focuses on making a novel Lanthanum Phosphate-based durable and cost-effective crucible for high temperatureapplications such as fabrication processes of advance functional materials. A crucible is designed and fabricated by using threeparts die following by powder metallurgical technique. Stepwise sintering was used to sinter the crucible. The synthesizedcrucible was then exposed to several tests to assess its structure, surface topography, durability, thermal expansion, andthermal shock resistance. Thermogravimetric analysis revealed a smaller mass loss of about 9.7%. Scanning electronmicroscope (SEM) analysis showed a spherical structure with pores enough to make a compact structure. It is also observedthat the Lanthanum Phosphate-based crucibles have high non wettability after pouring out the molten magnesium and foundthermal shock resistant. Interestingly, the crucible retained its original shape without failure up to 4 cycles. These results showthat the synthesized Lanthanum Phosphate-based crucible is promising for high temperature applications.

Effect of different parameters and aging time on wear resistance and hardness of SiC-B4C reinforced AA6061 alloy

Hussein Alrobei 대한기계학회 2020 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.34 No.5

Applications of aluminum matrix composites are increasing in aerospace, automotive and biomedical fields because of their high strength, light weight and good wear resistant properties. From an intense literature review it is observed that various combinations of aluminum alloys have been developed through different manufacturing methodologies and their characteristics have been studied. It is identified that the study of a composite material consists of AA6061 alloy as a matrix material reinforced with SiC and B4C; a comparative experiment on sliding wear characteristics, hardness and wear resistant properties of nanocomposite with different aging time is a novel area yet to be undertaken. This paper presents a study of sliding wear characteristics in silicon carbide, boron carbide reinforcement prepared by using stir casting process. The hardness and wear resistance properties of nanocomposites with different aging time were measured in the work. When comparatively analyzed with AA6061, AA6061 reinforced with silicon carbide, AA6061 reinforced with boron carbide exhibited a steady and higher hardness than the other two metal composites. Also, we observed that when sliding wear characteristics are compared, the AMC reinforced with boron carbide exhibits an optimum wear rate. The optimal values of control parameters in wear rate and friction coefficient for boron carbide reinforced aluminum matrix composites are determined by response surface methodology. The control parameters considered are applied load, speed, weight % of reinforcement and distance. The effect of control parameters on the output variables was investigated by analysis of variance (ANOVA) and response plot. Interestingly, 27 % increase in hardness value for B4C reinforced composite material at the aging time of 200 minutes was observed. Furthermore, wear rate for B4C reinforced composite material was four times reduced as compared to monolithic AA6061. These improvements may be attributed to the homogeneous particle size, particle distribution without agglomeration and optimized parameters.

Structural and mechanical properties of friction stir welded Al2O3 and SiC reinforced Al 7075 alloys

Jarair Shafique,Hussein Alrobei,Aneela Wakeel,Rizwan Ahmed Malik,Azhar Hussain,Jaehwan Kim,무하마드 라티프 대한기계학회 2021 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.35 No.4

Al 7075 of 4 mm thickness plates were welded by using ceramic particles of micron size. Different revolution speed, ranging from 1600 to 2000 RPM and transverse speed of 17 to 35 mm/min were applied. The sound weld is achieved at revolution speed of 1600 RPM and transverse speed of 17 mm/min. In this work, ceramic particles of Al 2 O 3 and SiC were used to reduce the effect of the heat towards the base material during friction stir welding owing to their high friction coefficient and reasonable thermal conductivity and to enhance mechanical properties. Vickers microhardness test was performed on the plain, Al 2 O 3 , and SiC mixed Al 7075 welded samples. This test showed the welded joint by using Al 2 O 3 and SiC have 10 to 12 % increase in hardness than that of the joint without using particles. Tensile strength of welded joints without ceramics particles showed improved results. Dispersion of ceramics particles was examined by metallurgical microscope. Scanning electron microscope (SEM) images and fracture analysis of the stir welded zone and base materials were observed. The structuralproperty relationship of plain, Al 2 O 3 , and SiC mixed Al 7075 welded samples was discussed systematically and found that improvement in hardness for Al 2 O 3 , and SiC mixed Al 7075 welded samples was due to the higher thermal conductivities of added ceramic particles and precipitation strengthening mechanism. While, reduction in tensile strength ascribed to the formation of intermetallic compounds.

Synthesis and mechanical characterization of alumina based composite material for armor application

Muhammad Shahid,Rizwan Ahmed Malik,Hussein Alrobei,Jaehwan Kim,Muhammad Latif,Azhar Hussaina,Muhammad Uzair Iqbal,Azeem Hafiz 한양대학교 세라믹연구소 2021 Journal of Ceramic Processing Research Vol.22 No.2

This study focuses on development of advance ceramic with improved toughness which can be used as armor material forpersonnel protection. Toughness is the characteristics that defines material resistance to fracture. Ceramics are important classof materials with combination of good strength, toughness and with stand multiple-striking. In this study, three differentsamples i.e. alumina, Zirconia toughened alumina (ZTA), and alumina incorporated with SiC (SiCA); hexagonal shapesamples were made by dry pressing and sintered at 1600 oC in argon atmosphere. Microstructural characterization: SEM andOptical microscopy demonstrated fine grain size distribution in matrix phase. BSE images confirmed the presence of ZrO2particles. High porosity of about 6.35% was observed in SiCA samples. EDX analysis confirms the composition. Mechanicalcharacterization showed improved toughness at the expense of hardness. SiCA samples showed maximum value of hardnesswhile ZTA showed maximum toughness of 4.6 MPa·m1/2. The obtained properties are comparable to other ceramic materialsprepared by different methods.

Numerical and experimental evaluation of the mechanical behavior of Kevlar/glass fiber reinforced epoxy hybrid composites

Muhammad Nabeel,Muhammad Ali Nasir,Mariyam Sattar,Rizwan Ahmed Malik,Meshal Alzaid,Muhammad Shoaib Butt,Mohsin Saleem,Hussein Alrobei 대한기계학회 2020 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.34 No.11

Flexural, tensile, and impact strength of hybrid Kevlar/glass reinforced epoxy composite is studied. Six different types of hybrid composite material were manufactured by hand layup process using different compositions of Kevlar and glass fiber. Tensile, flexural and impact strengths of manufactured samples were investigated using standard tests and compared. It is observed that tensile strength is greater for combinations with higher percentage (%) of Kevlar fabric and decreases with an increase in the glass fabric %age. Flexural strength is higher for combinations with greater %age of glass fabric and decreases with an increase in the Kevlar fabric %age. From drop weight test, it is found from visual inspection that damaged area is increased with an increase in the glass fabric percentage. Numerical simulation model incorporated with elastoplastic material data successfully predicts tensile and flexural experimental results.

Drop Weight Impact and Tension-Tension Loading Fatigue Behaviour of Jute/Carbon Fibers Reinforced Epoxy-based Hybrid Composites

Zamurrad Arshad,Muhammad Ali Nasir,Yasir Baig,Muhammad Zeeshan,Rizwan Ahmed Malik,Khubab Shaker,Azhar Hussain,M. Latif,Maryam Sattar,Hussein Alrobei 한국고분자학회 2020 폴리머 Vol.44 No.5

This work focuses on the synthesis of a novel hybrid composite, fabricated by utilizing jute and carbon fibers reinforced epoxy composites through hand layup technique to replace pure carbon-epoxy fiber composites. The mechanical properties were evaluated by drop weight impact and tension-tension fatigue tests. The tension-tension fatigue test was conducted to monitor the dynamic stiffness and fatigue life degradation of hybrid composite materials by varying the layers of jute fiber. The maximum peak load during the impact test was observed as 1081.7 N in case of carbon/jute/ carbon/jute/carbon (CJCJC) stacking sequence composite materials. Finally, the surface morphology of hybrid composite materials was studied with scanning electron microscopy (SEM) after mechanical tests to check the delamination, fiber pull-out and matrix cracks. It can be concluded from the obtained mechanical results that the newly developed composite with 15% jute/carbon-epoxy hybrid materials has the potential to swap carbon-epoxy composite without much loss of fatigue life along with relatively enhanced ductility as well as impact strength.

Corrosion and wear behavior of TiN PVD coated 304 stainless-steel

Awais Awan,Riffat Asim Pasha,Muhammad Shoaib Butt,Rizwan Ahmed Malik,Ibrahim M Alarifi,Meshal Alzaid,무하마드 라티프,Ammar Naseer,Mohsin Saleem,Hussein Alrobei 대한기계학회 2020 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.34 No.8

Ti/TiN multilayered physical vapor deposition (PVD) coatings were deposited on stainless-steel by cathodic arc deposition method. Bare sample of stainless steel 304 was compared with monolithic TiN coating and TiN coating having 2, 4, 6 and 8 Ti interlayers. The properties like corrosion and wear resistance were studied and analyzed comparatively. Potentiodynamic polarization curves showed that highest corrosion resistance was indicated by TiN coating with 8 Ti interlayers. Sample having 8 Ti interlayers have high corrosion potential (E corr ) and low corrosion current density (I corr ) as compared to other samples. This may be attributed to the arrangement of interlayers that prevents the corrosive agents to penetrate surface. All multilayered coatings show better results than the substrate material. Pin on disk wear test revealed that coating having monolithic TiN layer have the lowest coefficient of friction and consequently have less wear volume and wear rate as compared to other coatings with Ti interlayers. These results made the investigated coated stainless steel 304 valuable for wide range of industrial applications that required wear and corrosion resistance.