@article { author = {Karkeh Abadi, M. and Najafizadeh, A. and Kermanpur, A. and Mazaheri, Y.}, title = {Effect of annealing process on microstructure and mechanical properties of high manganese austenitic TWIP steel}, journal = {International Journal of Iron & Steel Society of Iran}, volume = {8}, number = {1}, pages = {1-4}, year = {2011}, publisher = {Iron & Steel Society of Iran}, issn = {2981-0388}, eissn = {2981-0396}, doi = {}, abstract = {In the present study, the influence of annealing temperature on mechanical properties and the microstructure of a high manganese austenitic steel (Fe-30Mn-4Al-4Si-0.5C) was investigated. X-ray diffractometry, optical and scanning electron microscopy, hardness and tensile tests were used to analyze the relationship between mechanical properties and microstructure after annealing process. The results indicated an optimum combination of strength and elongation under the condition of high cold rolling reduction with subsequent annealing in the partial recrystallization region.}, keywords = {High manganese steel,Stacking fault energy,Mechanical twinning,Mechanical properties}, title_fa = {Effect of annealing process on microstructure and mechanical properties of high manganese austenitic TWIP steel}, abstract_fa = {}, keywords_fa = {}, url = {https://journal.issiran.com/article_6370.html}, eprint = {https://journal.issiran.com/article_6370_5206ca5f9118787f6b4fd8ab8d8b6982.pdf} } @article { author = {Soltan Attar, S. and Monshi, A. and Meratian, M.}, title = {The influence of TiO2 and Na2CO3 on the viscosity and crystallization behavior of mold powders}, journal = {International Journal of Iron & Steel Society of Iran}, volume = {8}, number = {1}, pages = {5-11}, year = {2011}, publisher = {Iron & Steel Society of Iran}, issn = {2981-0388}, eissn = {2981-0396}, doi = {}, abstract = {Mold powders are fluxing agents used as raw materials in the steel industry, which play very important role in processing stability and final surface quality of a product. Surface quality depends particularly on the viscosity and the heat transfer of infiltrated mold flux between the mold wall and the solidified steel shell. Heat flux across the interfacial gap depends on thermal properties of slag layer and its thickness, which is affected by slag properties such as melting, crystallization behavior, and temperature-dependent viscosity. Among all of the components of these powders, fluorine mainly controls the viscosity, solidification temperature and crystallization behavior of mold flux films. However, the volatilization and acidification of the fluoride is a significant health hazard and causes environmental pollution and intensifies the erosion to continuous caster. In this study, TiO2 is used as a substitution to fluorine in commercial start flux. The substitution possibility was examined by measuring the viscosity and crystallization behavior, when it was compared with the properties of industrial powder. In present study, devitrification has been investigated by DTA non-isothermal experiments. It has been shown that titanium dioxide tends to increase crystallization temperature with increasing the formation of perovskite crystalline phase and this causes a decrease in heat flux between the strand and the copper mold. On the other hand, slag viscosity was decreased with increasing titanium dioxide and Na2CO3 content. Further XRD characterizations have provided a similar fraction of crystalline phases through Riaz method in the industrial powder and low fluorine sample with 8wt% TiO2.}, keywords = {Mold powder,Crystallization,Viscosity,Fluorine}, title_fa = {The influence of TiO2 and Na2CO3 on the viscosity and crystallization behavior of mold powders}, abstract_fa = {}, keywords_fa = {}, url = {https://journal.issiran.com/article_6371.html}, eprint = {https://journal.issiran.com/article_6371_e536a675f87dc186d78f2e3233731351.pdf} } @article { author = {Arefpour, A. and Monshi, A. and Saidi, A. and Khayamian, T.}, title = {Producing low fluorine mold powder by replacing CaF2 with Na2CO3, ZnO and Fe2O3}, journal = {International Journal of Iron & Steel Society of Iran}, volume = {8}, number = {1}, pages = {12-18}, year = {2011}, publisher = {Iron & Steel Society of Iran}, issn = {2981-0388}, eissn = {2981-0396}, doi = {}, abstract = {Mold powders in continuous casting of steel contain fluorine through mainly CaF2 and occasionally NaF and Na3AlF6. Fluorine develops dangerous gases such as SiF4 and HF at high temperatures. In this study, CaF2 is partly replaced by substances such as Na2CO3, ZnO and Fe2O3.Sulfur free Portland cement clinker containing gypsum was used as a new product base. These additions developed comparable viscosity to the industrially used powder. In order to compare the viscosity of laboratory samples with the reference sample, study the crystalline behavior of samples, and compare them to the reference sample, there were performed sloped plate groove viscometer, XRD and SEM studies. It can be detected the Crystalline phases such as Gehlenite, Nepheline, Akermanite, Cuspidine, Na2ZnSiO4, Ca2ZnSi2O7, Ca3SiO5 and Mn3O4, Fe2SiO4. In order to develop less toxic mold powder in continues casting of steels, it is proposed being crystalline and glassy with comparable viscosity.}, keywords = {}, title_fa = {Producing low fluorine mold powder by replacing CaF2 with Na2CO3, ZnO and Fe2O3}, abstract_fa = {}, keywords_fa = {}, url = {https://journal.issiran.com/article_6372.html}, eprint = {https://journal.issiran.com/article_6372_74601ea7f7891759fec68ed1e91c0dee.pdf} } @article { author = {Kalantar, M. and Ghasemi, S. and Saadati, M.}, title = {The structure-property relationship in a desulfurised and degassing hot work W500 tool steel}, journal = {International Journal of Iron & Steel Society of Iran}, volume = {8}, number = {1}, pages = {19-25}, year = {2011}, publisher = {Iron & Steel Society of Iran}, issn = {2981-0388}, eissn = {2981-0396}, doi = {}, abstract = {The effect of secondary steelmaking processes such as desulphurization, removal of inclusions and vacuum degassing followed by hot forging and hardening heat treatment on the microstructure and mechanical properties of a hot-work w500 tool steel have been studied in details. In order to follow the progress of secondary steel making, the content of impurity elements such as S, P, O, H and N were measured. These elements influence the mechanical testing and the microstructure of the steel. The results show that desulfurization treatment can be accelerated at higher temperature of 1680 °C and 15 minutes holding time for silicon and aluminum with contents of 0.33% and 0.056% in the molten steel, respectively. In this condition, the removal percentage of sulfur has been reached to about 90% relative to the initial sulfur content. For the degassing sample A, the strength and the hardness, after hot working and quenching – tempering, have been increased from 976 to 2020 MPa and 29 to 52 RC, respectively. Whereas for the normal sample B, the associated strength and the hardness have been changed from 870 to 1845 MPa and 21 to 55 RC, respectively. The difference between mechanical properties of sample A and sample B cab be related to the presence of Al2O3 clusters, silicate inclusions, and a longer filamentary inclusion in the microstructure of sample B after hot-forging. Microstructural observations show that the morphology of pearlite in the forged sample A is more uniform and carbide particles are also much finer than these particles in the non-degassing forged sample B.}, keywords = {}, title_fa = {The structure-property relationship in a desulfurised and degassing hot work W500 tool steel}, abstract_fa = {}, keywords_fa = {}, url = {https://journal.issiran.com/article_6373.html}, eprint = {https://journal.issiran.com/article_6373_8a41e70f941fe35fc7daa604ae882e91.pdf} } @article { author = {Rasti, J. and Najafizadeh, A. and Meratian, M.}, title = {Correcting the stress-strain curve in hot compression test using finite element analysis and Taguchi method}, journal = {International Journal of Iron & Steel Society of Iran}, volume = {8}, number = {1}, pages = {26-33}, year = {2011}, publisher = {Iron & Steel Society of Iran}, issn = {2981-0388}, eissn = {2981-0396}, doi = {}, abstract = {In the hot compression test friction has a detrimental influence on the flow stress through the process and therefore, correcting the deformation curve for real behavior is very important for both researchers and engineers. In this study, a series of compression tests were simulated using Abaqus software. In this study, it has been employed the Taguchi method to design experiments by the factors of material flow curve and the friction coefficient. The compression test was simulated up to the axial strain of 1 and then the deformation curve was extracted from the force-displacement plot of the strokes. Deviations between the deformation curves and the material flow curves were analyzed using Taguchi approach. Furthermore, the final shape of samples and friction coefficients were logically correlated. As a result, a new method was proposed in order to evaluate the material flow curve, based on the experimental data by the mathematical data manipulation.}, keywords = {Hot compression test,Friction,Stress strain curve,Taguchi method}, title_fa = {Correcting the stress-strain curve in hot compression test using finite element analysis and Taguchi method}, abstract_fa = {}, keywords_fa = {}, url = {https://journal.issiran.com/article_6374.html}, eprint = {https://journal.issiran.com/article_6374_44b99e06e066fa7ee24705f05935b39d.pdf} } @article { author = {Rounaghi, S. and Kiani-Rashid, A.}, title = {The effect of quenching media and annealing temperature on graphitization transformation kinetic of CK100 tool steel}, journal = {International Journal of Iron & Steel Society of Iran}, volume = {8}, number = {1}, pages = {34-38}, year = {2011}, publisher = {Iron & Steel Society of Iran}, issn = {2981-0388}, eissn = {2981-0396}, doi = {}, abstract = {In this research, graphitization transformation of a commercial hypereutectoid steel called CK100 was studied by the dilatometric experiments at the range of 600 – 700 °C from prior martensitic structure. Also the effect of quenching media on the initial graphitization time and completion of transformation has been discussed. Also, graphitization transition from the different prior microstructures was studied using microscopic observations. Analyzing dilatometric data acquisitions confirmed good following results from Johnson–Mehl–Avrami equation. By calculating Avrami exponent, following of transformation kinetic from diffusion controlled nucleation and growth was resulted. Also, the minimum time for completion graphitization transformation was concluded about 45 hrs relative to the water quenched specimen after annealing at 670 °C.}, keywords = {Graphitization,CK100,Microstructure,martensite}, title_fa = {The effect of quenching media and annealing temperature on graphitization transformation kinetic of CK100 tool steel}, abstract_fa = {}, keywords_fa = {}, url = {https://journal.issiran.com/article_6375.html}, eprint = {https://journal.issiran.com/article_6375_c5ee8692321084317d675efa1e2f7c70.pdf} } @article { author = {Biglar, S. and Nemati, A. and Sarpoolaky, H. and Souri, A.}, title = {Effects of Cr2O3 on physical and mechanical properties of in-situ spinel containing castable}, journal = {International Journal of Iron & Steel Society of Iran}, volume = {8}, number = {1}, pages = {39-42}, year = {2011}, publisher = {Iron & Steel Society of Iran}, issn = {2981-0388}, eissn = {2981-0396}, doi = {}, abstract = {Increasing demands for cement, iron and steel industries for refractories with suitable workability in severe conditions (without any environmental risks), make the refractories’ researches to be an active area. Refractories containing Spinel has been developed with addition of chromia as a substitute in refractories using Magnesite - chromite. In this research, different amounts of Cr2O3 were applied in situ spinel containing castable and its effects on the physical and mechanical properties of the system were investigated. After mixing the raw materials, they were poured into the mold, using casting and vibrating methods. After drying samples at 110 °C, sintering process was conducted at 1400 and 1600 °C. Physical and mechanical properties were measured (including balk density, apparent porosity and cold crushing strength (CCS)). X-ray diffraction analysis (XRD) and Scanning Electron Microscope (SEM) were used to study the formed phases and microstructure. The results indicate that increasing the amount of Cr2O3, strength, bulk density and apparent porosity were decreased. Change in the apparent porosity was due to filling properties of Cr2O3 at low temperature and it seems to be related to the liquid phase sintering at high temperature. The data indicated that the CCS was increased by increasing Cr2O3 content and temperature. The XRD pattern showed that MgAl2O4, Mg(Al,Cr)2O4 and (Al1- xCrx)2O3 were the main detected phases in the system.}, keywords = {Chromium oxide,Spinel,Castable,XRD,SEM}, title_fa = {Effects of Cr2O3 on physical and mechanical properties of in-situ spinel containing castable}, abstract_fa = {}, keywords_fa = {}, url = {https://journal.issiran.com/article_6376.html}, eprint = {https://journal.issiran.com/article_6376_d358baa663b20d45c722e9d10f4ec175.pdf} }