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The Materials Science Laboratory (MSL) of the European Space Agency is a payload on board the International Space Station for materials science experiments in low gravity.
It is installed in NASA's first Materials Science Research Rack which is placed in the Destiny laboratory on board the ISS. Its purpose is to process material samples in different ways: directional solidification of metals and alloys, crystal growth of semi-conducting materials, thermo-physical properties and diffusion experiments of alloys and glass-forming materials, and investigations on polymers and ceramics at the liquid-solid phase transition. [1]
MSL was built for ESA by EADS Astrium in Friedrichshafen, Germany. It is operated and monitored by the Microgravity User Support Center (MUSC) of the German Aerospace Center (DLR) in Cologne, Germany.
MSL was launched with Space Shuttle Discovery on its STS-128 mission at the end of August 2009. It was transferred from the Multi-Purpose Logistics Module to the Destiny Laboratory shortly after the shuttle docked at the International Space Station some two days after launch. After that the commissioning activities started to check out first the functionality of the Materials Science Research Rack and MSL inside MSRR. The commissioning included the processing of the first two samples which took place at the beginning of November. After bringing those two samples back to ground for analysis by the scientists the rest of the samples from batch 1 will be processed in early 2010.
The Materials Science Laboratory (MSL) facility is the contribution of the European Space Agency to NASA's MSRR-1. It occupies one half of an International Standard Payload Rack.
The MSL consists of a Core Facility, together with associated support sub-systems. The Core Facility consists mainly of a vacuum-tight stainless steel cylinder (Process Chamber) capable of accommodating different individual Furnace Inserts (FIs), within which sample processing is carried out. The processing chamber provides an accurately controlled processing environment and measurement of microgravity levels. It can house several different Furnace Inserts. During the first batch of experiments the Low Gradient Furnace (LGF) is installed. Another furnace, the Solidification and Quenching Furnace (SQF) is already produced and waiting on ground for future operations. The FI can be moved with a dedicated drive mechanism, to process each sample according to requirements from the scientists. Processing normally takes place under vacuum.
The Core Facility supports FIs with up to eight heating elements, and provides the mechanical, thermal and electrical infrastructure necessary to handle the FIs, the Sample Cartridge Assembly (SCA), together with any associated experiment-dedicated electronics that may be required.
A FI is an arrangement of heating elements, isolating zones and cooling zones contained in a thermal insulation assembly. On the outer envelope of this assembly is a water-cooled metal jacket forming the mechanical interface to the Core Facility.
The major characteristics of the two produced Furnace Inserts are:
The LGF is designed mainly for Bridgman crystal growth of semiconductor materials. It consists of two heated cavities separated by an adiabatic zone. This assembly can establish low and precisely controlled gradients between two very stable temperature levels.
The SQF is designed mainly for metallurgical research, with the option of quenching the solidification interface at the end of processing by quickly displacing the cooling zone. It consists of a heated cavity and a water-cooled cooling zone separated by an adiabatic zone. It can establish medium to steep temperature gradients along the experiment sample. For creating large gradients, a Liquid Metal Ring enhances the thermal coupling between the SCA and the cooling zone. [2]
The samples to be processed are contained in experiment cartridges, the SCAs, that consist of a leak-tight tube, crucible, sensors for process control, sample probe and cartridge foot (i.e. the mechanical and electrical interface to the process chamber). The MSL safety concept requires that experiment samples containing toxic compounds are contained in SCAs that support the detection of potential leaks. The volume between the experiment sample and the cartridge tube is filled with a pre-defined quantity of krypton, allowing leak detection by mass spectrometry. However the first batch of experiments does not contain any toxic substances.
Up to 12 scientific thermocouples provide the sample's temperature profile and allow differential thermal analysis. [2]
Materials Science Laboratory - Columnar-to-Equiaxed Transition in Solidification Processing (CETSOL) and Microstructure Formation in Casting of Technical Alloys under Diffusive and Magnetically Controlled Convective Conditions (MICAST) are two investigations which will examine different growth patterns and evolution of microstructures during crystallization of metallic alloys in microgravity.
MICAST studies microstructure formation during casting of technical alloys under diffusive and magnetically controlled convective conditions. The experimental results together with parametric studies using numerical simulations, will be used to optimize industrial casting processes. MICAST identifies and controls experimentally the fluid-flow patterns that affect microstructure evolution during casting processes, and to develop analytical and advanced numerical models. The microgravity environment of the International Space Station is of special importance to this project because only there are all gravity-induced convections eliminated and well-defined conditions for solidification prevail that can be disturbed by artificial fluid flow being under full control of the experimenters. Design solutions that make it possible to improve casting processes and especially aluminium alloys with well-defined properties will be provided. MICAST studies the influence of pure diffusive and convective conditions on aluminium-silicon (AlSi) and aluminium-silicon-iron (AlSiFe) cast alloys on the microstructure evolution during directional solidification with and without rotating magnetic field.
The major objective of CETSOL is to improve and validate the modelling of Columnar-Equiaxed Transition (CET) and of the grain microstructure in solidification processing. This aims to give industry confidence in the reliability of the numerical tools introduced in their integrated numerical models of casting, and their relationship. To achieve this goal, intensive deepening of the quantitative characterization of the basic physical phenomena that, from the microscopic to the macroscopic scales, govern microstructure formation and CET will be pursued. CET occurs during columnar growth when new grains grow ahead of the columnar front in the undercooled liquid. Under certain conditions, these grains can stop the columnar growth and then the solidification microstructure becomes equiaxed. Experiments have to take place on the ISS due to the long-duration required to solidify samples with the objective to study the CET. Indeed, the length scale of the grain structure when columnar growth takes place is of the order of the casting scale rather than the microstructure scale. This is due to the fact that, to a first approximation, it is the heat flow that controls the transition rather than the solute flow. Experimental programs are being carried out on aluminium-nickel and aluminium-silicon alloys. [3]
In metalworking and jewelry making, casting is a process in which a liquid metal is delivered into a mold that contains a negative impression of the intended shape. The metal is poured into the mold through a hollow channel called a sprue. The metal and mold are then cooled, and the metal part is extracted. Casting is most often used for making complex shapes that would be difficult or uneconomical to make by other methods.
Heat treating is a group of industrial, thermal and metalworking processes used to alter the physical, and sometimes chemical, properties of a material. The most common application is metallurgical. Heat treatments are also used in the manufacture of many other materials, such as glass. Heat treatment involves the use of heating or chilling, normally to extreme temperatures, to achieve the desired result such as hardening or softening of a material. Heat treatment techniques include annealing, case hardening, precipitation strengthening, tempering, carburizing, normalizing and quenching. Although the term heat treatment applies only to processes where the heating and cooling are done for the specific purpose of altering properties intentionally, heating and cooling often occur incidentally during other manufacturing processes such as hot forming or welding.
STS-50 was a NASA Space Shuttle mission, the 12th mission of the Columbia orbiter. Columbia landed at Kennedy Space Center for the first time ever due to bad weather at Edwards Air Force Base caused by the remnants of Hurricane Darby.
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STS-83 was a NASA Space Shuttle mission flown by Columbia. It was a science research mission that achieved orbit successfully, but the planned duration was a failure due to a technical problem with a fuel cell that resulted in the abort of the 15 day duration. Columbia returned to Earth just shy of four days. The mission was re-flown as STS-94 with the same crew later that year.
STS-94 was a mission of the United States Space Shuttle Columbia, launched on 1 July 1997.
STS-87 was a Space Shuttle mission launched from Launch Complex 39B of the Kennedy Space Center on 19 November 1997. It was the 88th flight of the Space Shuttle and the 24th flight of Columbia. The mission goals were to conduct experiments using the United States Microgravity Payload (USMP-4), conduct two EVAs, and deploy the SPARTAN-201 experiment. This mission marked the first time an EVA was performed from Columbia. EVAs from Columbia were originally planned for STS-5 in 1982 and STS-80 in 1996, but were canceled due to spacesuit and airlock problems, respectively. It also marked the first EVA conducted by a Japanese astronaut, Takao Doi.
In physics and materials science, a drop tower or drop tube is a structure used to produce a controlled period of weightlessness for an object under study. Air bags, polystyrene pellets, and magnetic or mechanical brakes are sometimes used to arrest the fall of the experimental payload. In other cases, high-speed impact with a substrate at the bottom of the tower is an intentional part of the experimental protocol.
Space manufacturing or In-space manufacturing is the fabrication, assembly or integration of tangible goods beyond Earth's atmosphere, involving the transformation of raw or recycled materials into components, products, or infrastructure in space, where the manufacturing process is executed either by humans or automated systems by taking advantage of the unique characteristics of space. Synonyms of Space/In-space manufacturing are In-orbit manufacturing, Off-Earth manufacturing, Space-based manufacturing, Orbital manufacturing, In-situ manufacturing, In-space fabrication, In-space production, etc.
A foundry is a factory that produces metal castings. Metals are cast into shapes by melting them into a liquid, pouring the metal into a mold, and removing the mold material after the metal has solidified as it cools. The most common metals processed are aluminum and cast iron. However, other metals, such as bronze, brass, steel, magnesium, and zinc, are also used to produce castings in foundries. In this process, parts of desired shapes and sizes can be formed.
In metallurgy and materials science, annealing is a heat treatment that alters the physical and sometimes chemical properties of a material to increase its ductility and reduce its hardness, making it more workable. It involves heating a material above its recrystallization temperature, maintaining a suitable temperature for an appropriate amount of time and then cooling.
Spray forming, also known as spray casting, spray deposition and in-situ compaction, is a method of casting near net shape metal components with homogeneous microstructures via the deposition of semi-solid sprayed droplets onto a shaped substrate. In spray forming an alloy is melted, normally in an induction furnace, then the molten metal is slowly poured through a conical tundish into a small-bore ceramic nozzle. The molten metal exits the furnace as a thin free-falling stream and is broken up into droplets by an annular array of gas jets, and these droplets then proceed downwards, accelerated by the gas jets to impact onto a substrate. The process is arranged such that the droplets strike the substrate whilst in the semi-solid condition, this provides sufficient liquid fraction to 'stick' the solid fraction together. Deposition continues, gradually building up a spray formed billet of metal on the substrate.
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Dual-phase steel (DP steel) is a high-strength steel that has a ferritic–martensitic microstructure. DP steels are produced from low or medium carbon steels that are quenched from a temperature above A1 but below A3 determined from continuous cooling transformation diagram. This results in a microstructure consisting of a soft ferrite matrix containing islands of martensite as the secondary phase (martensite increases the tensile strength). Therefore, the overall behaviour of DP steels is governed by the volume fraction, morphology (size, aspect ratio, interconnectivity, etc.), the grain size and the carbon content. For achieving these microstructures, DP steels typically contain 0.06–0.15 wt.% C and 1.5-3% Mn (the former strengthens the martensite, and the latter causes solid solution strengthening in ferrite, while both stabilize the austenite), Cr & Mo (to retard pearlite or bainite formation), Si (to promote ferrite transformation), V and Nb (for precipitation strengthening and microstructure refinement). The desire to produce high strength steels with formability greater than microalloyed steel led the development of DP steels in the 1970s.
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The International Space Station is a platform for scientific research that requires one or more of the unusual conditions present in low Earth orbit. The primary fields of research include human research, space medicine, life sciences, physical sciences, astronomy and meteorology. The 2005 NASA Authorization Act designated the American segment of the International Space Station as a national laboratory with the goal of increasing the use of the ISS by other federal agencies and the private sector.
Selective laser melting (SLM) is one of many proprietary names for a metal additive manufacturing (AM) technology that uses a bed of powder with a source of heat to create metal parts. Also known as direct metal laser sintering (DMLS), the ASTM standard term is powder bed fusion (PBF). PBF is a rapid prototyping, 3D printing, or additive manufacturing technique designed to use a high power-density laser to melt and fuse metallic powders together.
ELIPS - European Programme for Life and Physical Sciences in Space and applications utilising the International Space Station started in 2001 and was intended to cover the activities for the following 5 years. This Microgravity Programme at the European Space Agency (ESA) is an optional programme, with currently 17 ESA member states participating. The ELIPS programme prepares and performs research on the International Space Station, and other uncrewed mission platforms like Sounding Rockets, in fundamental and applied life and physical sciences. ELIPS is the continuation of the earlier European microgravity programmes EMIR 1&2, and the Microgravity Facilities for Columbus, MFC.
The following page is a list of scientific research that is currently underway or has been previously studied on the International Space Station by the European Space Agency.