فهرس المقالات microstructures

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  1 - Effect of Processing Parameters on Properties of Friction Stir Welded Joints of Aluminium Alloys AA7075- T651 and AA6061-T6
  H. S. Patil Neelsai Sharma Kairav Patel Abhishek Patel Viral Patel Chetan Patil
  In the present investigation the mechanical behaviour of AA7075T651 and AA6061T6 aluminium alloys plates joined by friction stir welding (FSW) were evaluated. The effects of weld process parameter like tool rotation speed 650-1000 rpm and weld speed 30-40mm/min with squ أکثر

  In the present investigation the mechanical behaviour of AA7075T651 and AA6061T6 aluminium alloys plates joined by friction stir welding (FSW) were evaluated. The effects of weld process parameter like tool rotation speed 650-1000 rpm and weld speed 30-40mm/min with square trapezoidal pin profile on mechanical properties were investigated. The welded joints were tested by means of by X-ray radiography, tensile, hardness and optical microscopy testing. The radiography revealed the presence of internal in FS welds and observed that increasing transverse speed increases the occurrence of weld defects. The hardness was found to be mixed effect with respect to tool rotations and transverse speed for similar FSW joints. But in dissimilar FSW joints, hardness decreases with increasing tool speed and weld speed and it was strongly affected by precipitate distribution. Difference in grain size and distribution was observed for different ranges of rotation and weld speed. تفاصيل المقالة
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  2 - Influence of Cr dopant on the microstructure and optical properties of ZnO nanorods
  Saeed Safa A. Masoudi Nejad
  One-dimensional (1D) undoped and Cr doped ZnO nanorods with average length of 1 µm and diameter of 80 nm were synthesized using hydrothermal method where a fast growth of ZnO nanorods on the seed layer was observed. Afterwards, the effects of Cr dopant on structur أکثر

  One-dimensional (1D) undoped and Cr doped ZnO nanorods with average length of 1 µm and diameter of 80 nm were synthesized using hydrothermal method where a fast growth of ZnO nanorods on the seed layer was observed. Afterwards, the effects of Cr dopant on structural, surface morphology and optical properties of nanorods were studied using X-ray diffraction (XRD), scanning electron microscopy (SEM) and ultra-violet visible (UV-Vis) spectroscopy. The results showed that ZnO has a wurtzite hexagonal structure and that the Cr atoms were well incorporated into the ZnO crystal structure. Moreover, it was found that the Cr atoms could facilitate the preferential growth of nanorods in C-axis. Also, it was concluded from optical properties that doped ZnO nanorods was so appropriate for photocatalytic applications because the optical band gap. For example, the calculated band gap of ZnO nanorod decreased from 3.12 eV for pure ZnO nanorods to about 2.41eV for 3 at. % Cr doped ZnO nanorods which is quite enough to be activated even at visible (550nm) light for photocatalyst aims. تفاصيل المقالة
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  3 - Microstructure analysis of Zarab region, south of Kerman
  Farnaz Iranmanesh Amir Shafiei Bafti Sohrab Shahriari Mohsen Pourkermani
  Zarab region situated in south of Baft city and Northern Boundary of Sanandaj-Sirjan zone. Petrographical studies indicate the metamorphism grade of Rock units is about of moderately green schist facies and contain of: orthogenesis, Marble and abundance schist>s in m أکثر

  Zarab region situated in south of Baft city and Northern Boundary of Sanandaj-Sirjan zone. Petrographical studies indicate the metamorphism grade of Rock units is about of moderately green schist facies and contain of: orthogenesis, Marble and abundance schist>s in mentioned region. flow structures are seen In the mentioned rock unites specially in marble rock unite. Microstructural studies show various microstructures as like S-C structures, σ and δ structures Mica Fishes in mica schist>s which those indicate dextral shear stress sense, which caused Microstructures. The amounts of tension strains in normal section that prepared from oriented samples indicate prolate form strain ellipsoid parallel to schistosity fabrics. Field studies show, which the thrust faults, have a dextral movement (co orientation with microstructures shear sense), similar orientation and slip movement and absence of fault plan erosion. Varieties between faulting deformation (brittle deformation) and shear sense of microstructures (ductile deformation), reveal two deformation phase with a nonconcurring deformation time. تفاصيل المقالة