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Vacuum Systems and Technologies For VACUUM SYSTEMS AND TECHNOLOGIES FOR METALLURGY HEAT TREATMENT 2 ALD Headquarters ALD Vacuum Technologies Hanau, Germany Contents 3 History 4 Know-How Is Our Business 6 Worldwide Customer Sales & Service 7 METALLURGY 8 Vacuum Induction Melting and Casting (VIM/VIDP) 10 Electroslag Remelting (ESR) 22 Vacuum Arc Remelting (VAR) 30 Electron Beam Melting (EB) 36 Vacuum Investment Casting (VIM-IC) 40 Powder Metallurgy 46 Vacuum Turbine Blade Coating (EB/PVD) 54 Solar Silicon Melting and Crystallization Technology 62 Hot Isothermal Forging (HIF) 64 Induction Heated Quartz Tube Furnaces (IWQ) 66 High Vacuum Resistances Furnaces (WI) 68 HEAT TREATMENT 70 Vacuum Hardening,Tempering 74 Vacuum Case Hardening 80 Sintering 88 OWN & OPERATE 92 4 History Deep-Rooted Competence The process and systems know-how available within ALD Vacuum Technologies is based on developments over the past 85 years successfully brought about by the firms Degussa, Heraeus and Leybold. During that period, these companies worked together in a number of ways. 1916 1987 HERAEUS enters the field of vacuum DEGUSSA AG acquires all shares of metallurgy when it succeeds in melting Leybold-Heraeus GmbH, which is then chromium-nickel alloys under vacuum renamed LEYBOLD AG. conditions. 1991 1930 Degussa spins off its Durferrit business LEYBOLD starts manufacturing including Degussa Industrial Furnaces, while industrial vacuum equipment. Leybold AG sheds its vacuum metallurgy division. The two spin-offs merge to form 1950 LEYBOLD DURFERRIT GmbH. DEGUSSA decides to build vacuum furnaces. 1994 The vacuum metallurgy and vacuum heat treatment businesses become part of the 1967 newly founded ALD Vacuum Technologies. E. Leybold Successors merge with Heraeus-Hochvakuum GmbH to form LEYBOLD-HERAEUS GmbH. Degussa, Heraeus and Metallgesellschaft hold equal interests in Leybold-Heraeus GmbH. 5 1998 2002 On August 3, 1998, Safeguard International Introduction of new heat treatment Fund, L.P., Wayne, PA, USA acquires all system, type ModulTherm®. shares of ALD Vacuum Technologies. 2003 1999 Cooperation with AFC Holcroft, Wixom, ALD Vacuum Technologies enters the Michigan. Own & Operate Business. 2005 2000 2 nd US Own & Operate factory started Decision about Own & Operate in USA. in Port Huron, Michigan. ALD enters into the vacuum coating business by acquiring all EB/PVD activities from Leybold AG. 2006 ALD Polska, another production site for 2001 ALD, started in Czosnow, Poland. Start up of the Own & Operate Business. 6 Know-How is our Business ALD Vacuum Technologies supplies ALD is noted for its superb know-how equipment and systems for thermal and basis, high investments in research and thermo chemical treatment of metallic development and its strategic alliances. materials in solid and liquid form. The Close collaborations with well-known company`s competence consists on the manufacturers in operator companies have one hand of its mastery in vacuum process strengthened its position as a supplier of technology and on the other hand of its key technologies to major growth markets. know-how in designing custom-tailored system solutions for use in this field. Worldwide Technology and Market Leader The company is a worldwide technology and market leader in the following fields: Vacuum Metallurgy Vacuum Heat Treatment This involves designing and supplying This includes vacuum furnaces for heat systems and processes for treating metallic treating metallic materials. Such equipment is materials in liquid form – particularly used for heat treating of tools, high precision vacuum systems for the melting, casting parts for engines and fuel injectors as well as and remelting of metals and alloys, metals for transmissions. Sintering of high strength for solar cells as well as special coating cemented carbides and special oxides is also equipment for turbine blades. a part of heat treatment. Worldwide Customer Sales & Service 7 ALD plants are built for operation around ALD services include professional support the clock, seven days per week. As and in emergencies as well as preventive when the need for service arises, a global maintenance for plant equipment and the network is available to send urgently needed refurbishment of older systems to boost spare parts or an experienced service plant availability to the highest possible level. technician. ALD has subsidiaries in 6 Our services at a glance: countries worldwide and representations in many others. Our marketing and service I Delivery of spare parts and consumables; network and replacement part stocks at I Repair services; stra tegic locations enable us to react at short I Maintenance and inspection; notice. Additionally, our headquarters in I Equipment refurbishment. Germany operate a customer support center with dozens of experts who assist whenever special know-how is required. Sales Offices, Engineering Facilities & Operator Companies Head Quarters Territories Covered by Representatives VACUUM METALLURGY The Development of New Vacuum Processes for Metallurgy Drives Technological Advances in Future Markets Vacuum Metallurgy VACUUM METALLURGY 9 Vacuum metallurgy is presently entering The resulting materials of high strength a new phase wherein it is assessing and reliability add to demanding the experience gained from continuously applications in the aerospace industries, developing established processes while the high-purity products contribute and joining together new process to new developments in electronics and combinations. Advanced vacuum offshore and energy applications. Each processes such as steel degassing and every technology has its pros and and ladle metallurgy, melting and cons, partially overlapping each other remelting, as well as casting and in their techno-economic potentials. metal-powder technology, have led Therefore, the proper selection of to high-quality metallurgical products technology is the most demanding task tailored to meet the ever-increasing the plant builder has to solve in close demands imposed upon them. New dialog with the producer of the materials processes are being developed that and the consumer. This particular will yield further improve ments as challenge is the keystone of the business well as entirely new products. philosophy of ALD Vacuum Technologies, Hanau / Germany. The use of these metal-making processes in modern, efficiently functioning production systems greatly reduces costs. The recycling of revert from the processing of costly materials contributes to the economy´s cost-effectiveness. Examples of the products that have been derived from these technologies include highly alloyed special steels and superalloys, refractory and reactive metals with ultrahigh purity and a fine grain structure, precision castings with Vacuum metallurgy for the airplane of the future. Concealed behind the directional and single-crystal structures, technical term, „vacuum melting and controlled solidification“ as well as „electron beam physical vapor deposition“ are path-breaking technologies for the energy saving forgings in near net shape, and high- airplane of the future. These vacuum metallurgical processes allow large-scale mass purity powder for homogeneous, high- production of turbine blades, which reduce fuel consumption by up to 30% and strength parts. emissions by 15% and more. VACUUM INDUCTION MELTING AND CASTING Vacuum Induction Melting (VIM/VIDP) Furnaces for Charge Weights from 1 kg up to 30 tons Vacuum Induction Melting Furnaces VIM 11 Vacuum induction melting (VIM) is one of the Vacuum induction melting makes possible most commonly used processes in secondary effective degassing of the melt and extra- metallurgy applied for refining treatment in ordinarily precise adjustment of alloy the liquid state and adjustment of chemical composition, since the temperature, vacuum, composition and temperature. To achieve gas atmosphere, pressure and material the increasing quality demands on the transport (e.g., through stirring of the bath) resulting material and at the same time can be adjusted independently of one I save raw materials such as alloying another. Besides the exact concentration elements due to higher yield; and of alloying elements, the content of trace I save energy, elements is also important for many alloys. Sampling the application of vacuum in the induction melting process is a must for many specialized Metallurgical Advantages materials. For example, vacuum induction are: melting is indispensable in the manufacture of special alloys, which must be melted I Melting under oxygen-free atmosphere, under vacuum or in an inert gas atmosphere this limits formation of non-metallic because of their reactivity with atmospheric oxide inclusions and prevents oxygen. The process is suitable for the oxydation of reactive elements; production of high-purity metals within an I Achievement of very close oxygen-free atmosphere. This limits the compositional tolerances and gas formation of non-metallic oxide inclusions. Temperature contents; measurement Current processing route for products cast from VIM/VIDP furnaces 12 I Removal of undesired trace elements Depending on the product and metallurgical with high vapour pressures; process, vacuum levels during the refining I Removal of dissolved gases e.g. phase are in a range of 10-1 to 10-4 mbar. oxygen, hydrogen, nitrogen; I Adjustment of precise and The following methods can be easily homogeneous alloy-composition and combined with the VIM system to produce melt temperature. clean melts: I Atmosphere control with low leak and For this reason,
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