Dry sliding adhesive wear behaviour of as-cast and austempered ductile iron (ADI) samples alloyed with manganese and copper was investigated in a pin-on-disc wear testing machine. As-cast samples suffered a rapid and continuous wear, while the austempered samples exhibited improved wear resistance on increasing the austempering temperature and time. ADI samples with higher copper plus manganese contents inherently possessed higher hardness due to presence of martensite in the ausferrite matrix. The wear conditions used in the present
study further promoted the formation of martensite under wear load and contributed much improved wear performance. In ADIs containing manganese only, wear process involved a mixed mechanism of oxidation and delamination. On combined alloying with copper and manganese, wear resistance increased considerably showing only mild oxidation and practically no delamination. The combinedly alloyed austempered samples exhibited even better wear resistance than that of cast and heat treated high manganese steel. Thus, the addition of manganese and copper in the experimental ductile irons assisted austempering by virtue of their synergistic effect on hardenability of Fe-C alloys and improving wear resistance through subsequent work hardening of the wear surface.

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Steel enjoys an unsurpassed wide range of properties: first of all its stiffness-strength-formability relationship contributes to featuring steel a high potential as versatile light-weight construction material. In this respect it pays to use steel, its price cannot be undercut without accepting compromises. This is topped by additional gains comprising high availability, reliability, excellent manufacturability and recyclability. Steel enjoys great popularity amongst designers, most of them are very familiar with it. In intermaterial competition, steel may not win in every single discipline, but steel is the undisputed champion in multi-discipline jobs. This makes steel an indispensable material.

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High nitrogen steels are commonly known for their excellent mechanical properties, i.e. strength and corrosion resistance. A state-of-the-art production routine is P-ESR melting (pressurised electro slag remelting). It is possible to manufacture both, austenitic as well as martensitic steels suitable for forging and hot rolling. Some basic knowledge of the material peculiarities is mandatory to avoid any potential issues during plastic deformation. The following paper provides an overview of the manufacturing of HNS as well as some properties to be considered for plastic deformation.

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Corrosion behavior of 19Cr-18Mn-0.69N austenitic stainless steel was studied by cyclic polarization technique in 3.5 % NaCl solution and was compared with that of other austenitic stainless steels having different compositions namely, AISI 316L and one with 14 Cr and  8% Mn, denoted 14Cr-8Mn in the following. The results showed that 19Cr-18Mn-0.69N austenitic stainless steel exhibits higher pitting resistance compared to that of other two alloys. SEM micrographs of 19Cr-18Mn-0.69N austenitic stainless steel after corrosion showed no pits at the alloy surface even when it was polarized beyond transpassive pitting potential. However severe attack was seen at the araldite-metal interface. But, in case of AISI 316L and 14Cr-8-Mn severe pitting attack was seen at the surface, whereas no attack was seen at araldite-metal interface. Critical crevice temperature for the three stainless steels was determined. 19Cr-18Mn-0.69N austenitic stainless steel was found to have good crevice corrosion resistance compared to other alloys investigated.

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The total amount of solid particles as a parameter influencing the viscosity and the foaming properties of the slag was investigated. In this context, the amount of these particles for different process conditions was quantified. In addition, the effect of the process conditions on the total amount of the particles was studied. More specifically, some parameter studies were carried out in oder to determine the influence of chromium oxide (Cr2O3) content, calcium oxide (CaO) content, basicity and temperature on the total amount of solid particles. The interactions between the process conditions were also taken into account.

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P91 steel is also known as modified 9Cr-1Mo (P91) steel is widely used as a structural material in the construction of power plant components. In high-Cr ferritic steels, toughness degradation in welds was caused by the presence of δ-ferrite phase in the martensite matrix. The δ-ferrite phase formation is influenced by factors such as chemical composition of welds, Creq and Nieq , heat input used during welding. As the δ-ferrite phase content increases there was reduction in toughness of welds below the specified requirement of 47 Joules as per the standard EN1557: 1997. The poor toughness of welds having δ-ferrite phase can be improved by prolonging the PWHT duration at 760°C. Flux system of consumables also influences the toughness of welds. Basic flux system produces welds having higher toughness than acidic flux system. This is due to microinclusion content of welds. The flux basicity, V and Nb content, and ferrite factor are interrelated and presented as a line diagram. The present study discusses about the role of chemical composition, and welding processes (SMAW and FCAW) on the formation of δ-ferrite phase in welds and its influence on toughness of welds.

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Rare earths (RE) have been used to improve the high temperature oxidation resistance of low alloy steel containing elements like Cr, Al, V and Mo. Further, the RE can be added either to the alloy or by applying as an oxide coating to the alloy surface. In this study the high temperature oxidation resistance of rare earth (RE) oxide coated 1Cr-0.3Mo-0.25V alloy was determined. This paper presents the influence of surface additions of nano-crystalline oxides CeO2 on the isothermal oxidation behavior of 1Cr-0.3Mo-0.25V alloys at temperatures ranging from 600 °C to 900 °C. The oxidation rate of RE oxide coated1Cr-0.3Mo-0.25V was significantly lower than that of the uncoated alloy. The improvements in oxidation resistance are the reduced oxidation rates and the increased oxide scale adhesion. Scanning electron microscopy (SEM), X-ray diffractometry (XRD), and electron probe micro analyzer (EPMA) were employed for these analyses. The scale formed in the presence of RE oxides was very thin, fine grained and adherent.

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Incremental forging processes like radial forging become more and more crucial in industry due to their outstanding economic performance, their high flexibility and their advantageous compressive stress states. However, nowadays a basic method to analyze forging processes, FEM simulation is still a very time consuming procedure and needs complex models to implement incremental processes. Especially long term studies with focus on tool temperature development during several hours of production cannot be performed with classical FEM models for radial forging. The main problem in modelling is the high operating frequency of the forging devices, which leads to small necessary time steps and, therefore, to inacceptable calculation time due to numerous simulations that have to be run to complete a cogging process sequence. Steady state in die temperature is often only reached after processing several workpieces. Hence, it is necessary to use a simplified FE-model of the forging process to predict the steady state temperature of the forging dies. In the present work a simplified FE-model is established to investigate the steady state temperature of the dies. This approach is verified by metallographic studies proving its accuracy.

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High-manganese steels are characterized by high ductility, strength and work hardening resulting from the formation of strain induced martensite (TRIP-effect) or twins (TWIP-effect). A third type is shear band induced plasticity (SIP) in Triplex steels. The Mn-content ranges from 15 to 30 %. Mn and additions of C, Si and Al exert a strong influence on the microstructure and the deformation mechanism and can accordingly affect both strength and ductility. The max. carbon content can be around 1.2 %. The main interest is currently concentrating on TWIP steels. Production of these grades via the conventional steelmaking routes can raise problems and, therefore, modifications and/or alternative production methods have to be applied. With respect to their extreme strength levels, high-Mn steels exhibit an extraordinary forming potential. Welding involves some specific challenges. The possible occurrence of delayed fracture is discussed. High-Mn steels have to compete with other lower alloy steels and special stainless grades with the same objective targets. Referring to this, the laboratory and industrial trials are to be continued in order to fully exploit the considerable market potential of the new steels.

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A process for electroless deposition of NiP films on a transparent non-conductive soda lime glass is investigated. The process requires at least two repetitive cycles of etching and activation. The annealing process of the NiP films at 400 and 600˚C has been studied and the optimal heat treatment condition has been established. Different Ni bath with different pH has been employed to assess the NiP deposition. Characterization of the deposits by optical and scanning electron microscopy has provided information on the nature of crystallites and on the surface topography.

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JSW Steel Limited is a 10.0 Mtpa integrated steel plant and 2 corex & 4 blast furnace forms the main iron making units. Sinter and pellet are the main iron bearing feed to iron making units. JSW Steel Limited operates with a 4.2x2 Mtpa pellet plant and the production rate of each pellet plant is ~500t/hr. Pellet plant utilizes 100% beneficiation plant (BP) product for pellet making. Beneficiation plant product size (pellet grade fines) is coarser (-45micron - 40 to 45%) in nature. Optimum particle size of the raw material is required to get the desired properties of the pellets. BP plant has set up two number of ball mill to get the optimum particle size for pellet making. Pelletisation studies were carried out in laboratory by varying the ball mill discharge size from 52 to 68% -45micron size to optimize the pellet grade fines size to achieve desired physical and metallurgical properties of the fired pellets. The desired physical and metallurgical properties of the pellets were obtained with the iron ore fineness 64% -45micron size due to presence of well balanced mineralogical phases.

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Failure assessment was made on cylindrical pressure vessels containing longitudinal weld misalignment performing finite element analysis (FEA) utilizing the Ansys software package. A 20° section of the cylindrical shell wall was modeled utilizing the plane strain element (plane 182) with the longitudinal weld in the centre of section. The weld misalignment was introduced by shifting the position of the cylindrical section on one side of the weld relative to the other section. Failure pressure estimates from FEA based on the global plastic deformation are found to be in good agreement with existing test results on vessels made of Afnor 15CDV6 steel and maraging steels.

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