Friction stir processing (FSP) is a surface treatment technology that can eliminate casting defects locally by refining microstructures, thereby improving the mechanical properties of material.

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Welding of super bainitic and triplex structure steels was studied using AWS A5.5 E11018-M and AWS A5.4 E312-17 electrodes. The existence of martensitic structure at the heat affected zone encourages the occurrence of cold cracking at the HAZ in welding of both super bainitic and triplex steels. Using E312-17 electrode renders the occurrence of cold cracks at the heat affected zone of these steels. The tensile strength of welded joints using E11018-M electrode is higher than that of the pure weld metal of E11018-M electrode. This could be attributed to the dilution of weld metal from the base metal especially carbon content. The V– notch impact test results using E312-17 electrode were slightly higher than that obtained using E11018-M electrode. This could be attributed to the occurrence of cold cracks using E11018-M electrode in addition to the tough austenitic weld metal using E312-17 electrode.

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In the present work, the effect of welding procedure on weldability of conventional high manganese steel compared with the recent developed ladle treated one. This research aims at disclosing the microstructure, hardness, impact toughness and tensile strength of the welded joints. The optical micrograph of the conventional high manganese steel welded joint without cooling between passes shows that the heat affected zone (HAZ) has a high density of carbides formed at the grain boundaries. However, cooling between passes using compressed air resulted in a decrease in the density of carbides formed at the grain boundaries of the HAZ. In the ladle treatment samples, the microstructure shows an increase the density of the eutectic phase of the HAZ as a result of welding without cooling. On the other hand, application of cooling using compressed air between passes results in a low density of the eutectic phase in the HAZ.

Application of cooling between deposited passes resulted in a significant improvement of the impact toughness of weldment in both conventional and ladle treated samples of high manganese steel. The result obtained by SEM observation shows the reduction of both carbides at the grain boundaries in HAZ of conventional high manganese steel and the eutectic phase in HAZ of ladle treated one.

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Due to rising raw material prices, the fullest possible recycling of metals is becoming increasingly important. For example, non-ferrous metals are pelleted for reprocessing before they are further processed.

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COPT Center offers the stage for Leybold’s video shooting for its newest vacuum product

Cooperation between Universities and industrial enterprises are much more common in other countries, such as Great Britain and the United States. In Germany, cooperation is mostly restricted to the technology level and the subsequent transfer of basic research knowledge gained at the universities to the mass production opportunities of industry.

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Results used to generate material cards for optimised simulation models

Before materials can be used for a particular application, their behaviour has to be analysed under different mechanical and climatic conditions. The results from static, dynamic and thermochemical tests form the basis for comprehensive material characterisations which are key to successful product development. As a leading provider of development services, ARRK Engineering has therefore established an in-house materials laboratory close to its headquarters in Munich. This enables car manufacturers, machine and plant engineering companies and also the aerospace industry to obtain all-round support from the ARRK Engineering specialists in this field. Moreover, the company plans to use the information from the tests to generate material cards with a view to optimising the simulation models for structural and crash calculations.

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Hot goods in aluminium

Photo: ZPF

Whether foil packaging or car body part – aluminium is indispensable as a light metal in many production sectors and branches of industry, despite new materials such as carbon fibre reinforced plastics. Efficient processing of aluminium is ensured by special, energy-saving melting furnaces for instance those produced at ZPF GmbH, located in the German federal state of Baden-Württemberg.

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Resistance against gouging and abrasive wear in impact crushing arms cast from Mn-steel, is related to variations of carbon, manganese and the microstructure of the cast steel. Additions of Boron, molybdenum and chromium to the plain Mn-steel casts (0.8-1.4%C-13%Mn) increase its wear resistance and fatigue life time during crushing operation due to enhancement of its strain hardeing capacity, grain refinement and strengthening by solid solution hardening of the matrix. This improvement is due to the intended change in the microstructure where precipitation of boron carbides and chromium carbides inside the austenitic matrix, grain refinement and increasing soluble carbon content in austenite phase is occurred. Solution treated Mn-steels (1050C, 2h, WQ) alloyed with boron showed crushing capacity of about 1200-1550 tones basalt per set depending on their compositions. The hardness of the as water quenched austenite is increased by about 25% to reach 397 HB when alloyed with 0.37%B. However work hardened matrix of Cr+Mo+B modified Mn-steel impact arms showed a bulk hardness of about 498 HB. The fatigue resistance of boron alloyed steel is increased to about 1.4 times over that measured for plain Mn-steel.

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Chips of various morphologies formed during surface grinding of cast AISI 409 stainless steel slabs have been examined in light microscope and SEM. Dynamic nucleation of fresh grains occur in the work hardened layer of chips of various morphologies, but growth of these grains on the chip surface is highly non-uniform. Iron rich oxide nodules also grow on the chip surface.

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Enameling steel has important applications in our daily life as in domestic appliances and industry (chemical, agro-food, storage tanks, heat exchangers..etc.) due to its outstanding properties resulting from combined advantages of steel and enamel. The combination of such steel and enamel provides durability and glossy appearance that withstand chemical corrosion, abrasion, thermal shocks and fire. The durability and quality of enameling process depends to a great extent on the quality of substrate (enamel steel). To ensure an acceptable quality of such steel to be enameled, care must be taken during steelmaking and refining such grade to obtain low carbon levels (0.03-0.05%max) and minimum count of inclusions. The morphology of inclusions is adjusted by Ca-cored wire feed technology however melt stirring using Argon is very useful to minimize inclusions and gas contents. Vacuum decarburization of steel melt to ensure low carbon levels prevents the black specks during firing of such steel sheets; however micro-alloying with 0.2-0.5% Ti or V stabilizes the rest of carbon and creates default sites for hydrogen after cold rolling to prevent fish scale phenomena after enameling. Assessment of inclusion counts and their morphology as well as distribution of carbides are carried out using scanning field electron microscopy and ASTM standard.

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Continuous casting, initially introduced in 1840, is an attractive method in mass producing semi-finished metal shapes (slabs, blooms, and billets) from molten metal. More than 50% of current world’s steel production is produced by continuous casting. Today, annually 750 million tons of steel in the steelmaking operation, 20 million tons of aluminum and many tons of other alloys are directly cast from molten metal by continuously casting method [1]. This paper presents a short review over the processes in consciously cast steel.

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