Through contact with radiation in space, space vehicles can corrode. This means changes in the physical, electrical and mechanical properties of structural, protection and isolation materials. Spacecraft nearer to earth are attacked by oxygen atoms of the topmost atmosphere, whereby organic material are affected the most. In manned space stations, organic gas emissions for the station itself also play a role. Contaminated substances under the influence of external radiation build up on the surface of the space station.
The project was defined as a technological development task. Decisive for the choice of this experiment was the absolute innovation of such a task setting, because similar devices for the usage on earth are too big and heavy.
Objectives
One of the main tasks of a material analysis station is the chemical diagnosis of material changes due to space corrosion. Other tasks include the chemical analysis of materials onboard the space station – e.g. crystals and molten baths – as well as the chemical analysis and isotope analysis of micro-metereoites. These tasks can only be executed with great difficulties on earth. Mostly the delivery of materials back to earth is not possible and even if this is the case, there’s a risk of contaminating (contamination of the surface with packaging material) the samples. On the other hand, corrosion effects are not fully reproducible in a laboratory.
In the framework of the AUSTROMIR 91 mission, the first part of this project was the building of a material analysis station for usage in space. It was planned to further develop and build the supplemental parts.
Functionality, Measuring principle
The chemical analysis was carried out based on the principle of secondary ion mass spectroscopy. A focused ion beam (“primary beam”) hits the sample’s surface, spurting out the sample’s atoms – a process that is known as ion beam atomization or sputtering. Some of these atoms are electrically charged (“secondary ions”) and the molecular mass can be directly determined using a mass spectrometer. The molecular mass determination delivers qualitative and quantitative information about the chemical and istopic composition of the sample areas affected by the ion beam. Through the deflection (rasterization) of the focused primary beam on the sample, a two-dimensional picture of the distribution of a particular element on the sample’s surface can be generated. Through the utilization of the atomization effect that the sample is exposed to, a depth profile of the elements can be analyzed for solid samples. Moreover, the spatial three-dimensional distribution of elements on surrounding areas on the sufrace can also be analyzed for such solid samples.
The core of the MIGMAS-A experiment is made up of a single ion emitter which is the one used for the LOGION apparatus. The ions are sucked through an extraction aperature on the tip and accelerated through another earthed aperature to the final energy beam. An additional aperature limits the beam divergence and concurrently functions as a ray stream monitor. The ion optical system further encompasses an asymmetrical electostatic single lense, an electrostatic X/Y-alignment system, and an X/Y-rasterization system. These are one-side earthed deflection plate pairs and are placed behind each other. An extraction optic for secondary ions is located in the space between the sample being investigated and the last raster electrode.
Only one sample can be scanned with this device configuration. The sample analysis and the possibility to switch samples are reserved for later expansion stages.
Shared equipments of the Austrian payload
DATAMIR
Results
The experiment has shown that such a complex precision instrument like an ion microscope can be brought into orbit without any damage. The stability of the newly developed minitiaturized liquid metal ion emitter in difficult operating conditions on board the space station has shown its application capability in a micro-analytical device. The device parameters and output data measured on MIR and identical with those measured on earth.
Controlling the device on board did not cause any problems. A cosmonaut can therefere complete complex tasks once the apparatus is completed into an ion microprobe mass spectrometer. After the AUSTROMIR 91 mission ended, the MIGMAS-A device was switched on another five times between January and July 1992 by the cosmonauts on board the station. For this reason one wanted to determine the long-term stability under the storage conditions on MIR and to establish the optimal system parameters in microgravity. These efforts were carried out free of charge by the Russian partners in the AUSTROMIR project and were as an advance for a planned future project.
Both the Austrian and the Russian experimenters hope on a continuation of the project, especially after the remarkable results of the MIGMAS-A apparatus. The device functioned faultlessly on board the space station till MIR crashed.
Practical application
Application ranges
- Space materials research in the field of activity of analysis from in space exposed or in space won materials
- Microelectronics, materials research, geology
- Ecology
Application target
- Increase of the safety of manned and unmanned space missiles
- Direct automatical analysis of materials and single elements via a to develope miniatur mass spectrometer with ionic probe
- Monitoring of the environment as well as the state of the materials, that reside at the surface or inside the space missiles
- The common commercial utilisation of the apparat MIGMAS (2nd phase)
- Material analysis using a miniaturised, portable apparat under non labor-conditions (field conditions, assembly-line, …)
- Environmental pollution monitoring
Direct interested institutions on the utilization of the experiment results
- Austrian Research Center Seibersdorf Ges.m.b.H., Seibersdorf
- Max-Planck-Institute for Atom Physics, Heidelberg, Germany
- Company of Hoerner & Sulger, Schwetzingen, Germany
- Institute for Communications Engineering and Wave Propagation of the Technical University Graz
- European, among Russian space organizations
Technical characteristics
The equipment MIGMAS-A consisted of the following units
Elektronic box with cables
- Ion gun
- Ion optic column consisted of
ray deflect system
adjustment system
focus system - Vacuum chamber
- Ion pump for maintenance of the vacuum
- Power supply unit
- Hight power supply unit
- Elektronic part consisted of
processing
activation of the ionic-optical system
data acquisition
data recording (memory cards)
interface to the system DATAMIR - Monitor
- Cable loom
- Return transport box for the memory cards
- Protective covering for the LCD-monitor
- Wrench for the protective covering
- Reserve fuses
| Mass: | 35.0 kg |
| Dimensions: | 628 mm x 260 mm x 580 mm |
| Power input: | 100 W |
Chart 2 (top right): Block diagram of the equipment MIGMAS-A
Chart 3 (bottom): Electrical principle schematic diagram of the project MIGMAS-A
Chart: BMBWK, Vienna
Experimenters
Part I:
o. Univ.-Prof. Dipl.-Ing. DDr. Willibald Riedler (project manager)
Dipl.-Ing. Robert Finsterbusch (project manager)
Dipl.-Ing. Franz Puerstl
Dipl.-Ing. Raimund Pammer
Wolfgang Schuetz
all: Institute for Communications Engineering and Wave Propagation, Technical University Graz
Part II:
Univ.-Prof. Dr. Friedrich Ruedenauer (project manager)
Dipl.-Ing. Dr. Peter Beck
Dr. Walter Steiger
Dipl.-Ing. M. Kammerhofer
all: Austrian Research Center Seibersdorf Ges.m.b.H., Seibersdorf