Bu calismada, matris yapisinin kuresel grafitli dokme demirin (KGDD) asinma davranisina, asinma sirasindaolusan surtunme katsayisina ve pim sicakligina etkisi arastirilmistir. Asinma testleri disk uzerinde pim turucihazda, 1 m s-1 kayma hizinda, 20, 40 ve 60 N yuk ve 3,6 km kayma mesafesinde, normal atmosfer sartlarindave oda sicakliginda gerceklestirilmistir. Asinma yuzeyleri tarama elektron mikroskobu (SEM) ile incelenmistir.Uygulanan yukun artmasina bagli olarak dokum durumu ferritik KGDD’in asinma hizi artarken, dokum durumuperlitik KGDD numunenin asinma hizi azalmaktadir. Testler, dokum durumu perlitik KGDD’nin surtunmekatsayisi ve surtunme sicakliginin, dokum durumu ferritik KGDD’den daha yuksek oldugunu gostermistir.Deneysel sonuclar, dokum durumu perlitik ve ferritik KGDD’lerin surtunme katsayisinin azalmasiyla, surtunmesicakliginin arttigini ortaya koymaktadir.
In this paper, the effect of manganese (wt%) and size of the Al 2 O 3 abrasive grains of abrasive wear behaviours of Al–Si–(0.16–0.76%) Mn alloy was examined. Abrasive wear experiments were conducted against abrasive Al 2 O 3 paper grains with diameters in the variety of 38–250 µm, under the normal load range of 10, 20 and 30 N and the sliding velocity of 0.1 m s −1 . Wear measurements have shown that the wear rate of the material is dependent on the manganese content and the abrasive grain size. The best wear resistance is in the content of 0.73 Mn, which is associated with increased toughness and strength. The Al–Si casting alloy which had 0.73% Mn content exhibited lower wear rate than the Al–Si–0.16/0.22/0.23% Mn alloys after scoured on fine abrasive Al 2 O 3 grains (<65 µm). Wear experiments achieved on Al 2 O 3 grains having sizes greater than 65 µm revealed that, the cast Al–Si– alloy which had 0.73% Mn content had lower wear rate than the cast Al–Si–0.16/0.22/0.23% Mn alloys.
In this paper, the effect of manganese (wt%) and size of the Al2O3 abrasive grains of abrasive wear behaviours of Al–Si–(0.16–0.76%) Mn alloy was examined. Abrasive wear experiments were conducted ...
Some novel long-chain nitrones, isoxazolines, and (1H-benzo[d]-imidazol-2-ylthio) derivatives were synthesized. Nitrones, N-{4-[2-(tetradecylthio)acetoxy]benzylidene}aniline oxide, and N-[4-(12-oxo-2,5,8,11-tetraoxadocosan-22-yloxy)benzylidene]aniline oxide were prepared via the reaction of β-phenylhydroxylamine with the corresponding aromatic aldehydes. The isoxazolines were prepared from undec-10-en-1-ol and benzonitrile-N-oxide which was generated in situ. The 1H-benzo[d]-imidazol-2-ylthio derivatives were synthesized via the replacement reaction of ω-bromo esters and 2-mercaptobenzimidazole.
Abstract Inconel 718 alloy is difficult to machine using conventional methods due to its physical properties. Thereby, additive manufacturing (AM) of IN718 components with near-net shapes has been excessively studied. Even though AM processes provide shape and size accuracy, there is still the need for the machining of the AM-processed components. Laser powder bed fusion (LPBF) has been successfully utilized to fabricate near-net shape IN718 components, moreover, the microstructure of LPBF-IN718 was unique owing to the AM processing, resulting in differences in grain size, grain boundary characteristics, and grain orientations. Furthermore, these microstructural characteristics are expected to alter the machining performance of IN718. Therefore, this study investigated the wire electro-discharge machining (WEDM) performance of LPBF-718 samples compared to wrought IN718 while focusing on the unique microstructure characteristics of LPBF-IN718 samples (lamella, single-crystal, ploy-crystal). Three different cutting strategies (rough, semi-finish, and finish) were implemented to understand the performance of the multi-pass cutting phenomenon and its effect on the surface of IN718. For all samples, rough (single pass) cutting displayed high roughness while finish (three passes) cutting exhibited good surface quality. Compositional analyses on the machined surface showed debris formation including Zn and Cu-containing recast material, indicating wire erosion. The surface of single-crystal LPBF-IN718 after the WEDM process was smooth owing to its big grain size and less amount of grain boundary, resulting in slow cutting speed but a good surface finish. Thus, this study, for the first time, investigated the effect of unique microstructural characteristics of LPBF-fabricated IN718 on WEDM performance and machined surface quality.
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