Materials Science Laboratory

MSRR-1 (NASA)

The Materials Science Laboratory (MSL) is a European Space Agency experiment on board the International Space Station . It was launched in August 2009 as part of the STS-128 mission with the Space Shuttle Discovery . The MSL is controlled and managed by the User Center for Space Experiments ( MUSC ) of the German Aerospace Center ( DLR ) in Cologne. The scientific ground support program is carried out by the Institute for Materials Physics in Space .

Mission history

As part of the STS-128 mission, MSL was transported to the ISS on August 29, 2009 with the Space Shuttle Discovery and transferred to the Destiny module. In October 2009, the MSRR-1 and MSL were activated for the first time and demonstrated their functionality. The first two experiments were successfully carried out at the beginning of November. The experiment samples will be brought back to Earth on the STS-129 shuttle mission and then evaluated by the participating scientists. In the first half of 2010, the remaining eleven samples from the first series of experiments (batch 1) will be processed. Further experiments are already in the planning stage (Batch-2).

purpose

MSL is used to melt and solidify conductive metals , alloys and semiconductors in extreme vacuum or in high-purity noble gas environments in weightlessness . In addition to experiments to better understand the influences of weightlessness on the structure development of metals in casting processes, the system opens up further possibilities for researching the thermophysical properties of alloys and glass-forming materials as well as the solid-liquid phase transitions in polymers and ceramics . The aim of the investigations is to expand the understanding of transition processes, (atomic) structures and material properties so that the calculation models can be improved. It should be possible to refine previous production methods, improve products and develop new ones.

MSL is the only experiment in the NASA Materials Science Research Rack installed in the Destiny laboratory on board the ISS. The integration of the rack was initially planned for the European Columbus research module , but has since been postponed to the American laboratory. The remote-controlled operation of the facility and the implementation of the scientific ground support program is the responsibility of ESA and is carried out by the User Center for Space Experiments (MUSC) of the German Aerospace Center (DLR) in Cologne. In addition to maintenance work, crew activity in space is essentially limited to inserting the experiment cartridges and connecting them to the measurement electronics.

construction

MSL consists of a core element and numerous auxiliary systems. The core element mainly consists of an airtight stainless steel chamber that can be placed under vacuum. In order to carry out different experiments, it can accommodate different furnace elements in which the samples are processed.

The chamber provides a precisely controlled environment for the experiments. The oven racks can be moved over the samples either very slowly or very quickly with two different drives. They can contain up to eight heating zones that can be controlled separately from one another. In addition, a precisely controlled magnetic field generator can generate a corresponding field in the samples. The experiments are carried out under vacuum. The contents of the chamber are initially released into space and then turbo molecular pumps ensure that the vacuum remains below 10 ⁻⁴ mbar during processing .

Two oven racks are currently available, one of which (Low Gradient Furnace - LGF) is in space for the first set of experiments. The second furnace (Solidification and Quenching Furnace - SQF) will be started later for the next experiments.

An oven insert consists of heating elements, insulation zones and cooling zones and is enclosed in an insulation housing. On the outside, various connections establish the electrical and cooling water connection to the system.

rehearse

The samples are enclosed in special containers, the Sample Cartridge Assemblies - SCA . These consist of a sealed tube, a crucible, various sensors and a head that makes mechanical and electrical contact with the system. MSL is generally also able to process toxic samples. These must contain krypton . During the experiments, a mass spectrometer then searches for traces of the gas in the main chamber in order to rule out a leak. However, the currently planned experiments do not contain any toxic samples.

Up to twelve temperature sensors are built into the SCAs for scientific monitoring of the experiments.

Experiments

The first MSL experiments were carried out as part of the ESA MAP (Microgravity Application Program). The ESA MAP projects are public-private partnerships between industry, universities, research institutions and national agencies.

The CETSOL (Columnar to Equiaxed Transition in Solidification Processing) and MICAST (Microstructure Formation in Casting of Technical Alloys under Diffusive and Magnetically Controlled Convective Conditions) projects investigate different growth structures and the development of the microstructure during the solidification of aluminum alloys. The aim is to gain a better understanding of the parameters and processes that influence the solidification of metal melts. With the help of the results, numerical models for predicting the internal structure of cast parts are to be checked and further developed. This serves to optimize previous casting processes in order to ultimately obtain products with better and specifically adjusted material properties.

The CETSOL experiment deals with the investigation of fundamental physical phenomena during the solidification of metal melts and their effects on the material properties.

MICAST investigates the formation and development of microstructures during the solidification of technical aluminum alloys under the influence of currents, such as those that occur during casting. In the experiment, the currents are simulated by a rotating magnetic field and the results are compared with samples that have solidified in zero gravity, flow-free.

These experiments can only be carried out on the ISS, as this is the only place where there is sufficient weightlessness available to investigate the issues. Research on the ISS enables controlled and precisely defined experimental procedures without the disruptive influence of gravity and thus offers ideal conditions for basic research.

Web links

MPLM transfer work in full swing . Raumfahrer.net, September 3, 2009

Individual evidence

↑ European laboratory for materials science experiments installed on the ISS. DLR, September 7, 2009, accessed on September 29, 2009 .
↑ ^a ^b Laboratory for materials science on the ISS put into operation. DLR, November 11, 2009, accessed on November 12, 2009 (German).
↑ ^a ^b ^c ^d Materials Science Laboratory. (PDF; 3 MB) ESA, accessed on September 29, 2009 .
^ Materials Science Research Rack-1 (MSRR-1). NASA August 21, 2009; archived from the original on July 9, 2009 ; accessed on September 29, 2009 .
↑ MSL-LGF: High temperature materials research onboard the ISS by means of resistance heated furnaces. DLR, accessed on September 29, 2009 .

[1] European laboratory for materials science experiments installed on the ISS. DLR, September 7, 2009, accessed on September 29, 2009 .

[DLR1-2] Laboratory for materials science on the ISS put into operation. DLR, November 11, 2009, accessed on November 12, 2009 (German).

[ESA_MSL-3] Materials Science Laboratory. (PDF; 3 MB) ESA, accessed on September 29, 2009 .

[4] Materials Science Research Rack-1 (MSRR-1). NASA August 21, 2009; archived from the original on July 9, 2009 ; accessed on September 29, 2009 .

[5] MSL-LGF: High temperature materials research onboard the ISS by means of resistance heated furnaces. DLR, accessed on September 29, 2009 .