Joining Technologies and Corrosion  
Alloy Design & Processing Technologies
Corrosion and Local Electrochemistry
Functional Surfaces in Reactive Environments
Joining & Interface Engineering
User Lab Metallography
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SUMMARY OF OUR SERVICES
 

We offer the following high-end services and materials analysis to your specialized needs:

 

Please consult our lab expert(s), as indicated below, for detailed information.

CORROSION MANAGEMENT & FAILURE ANALYSIS

Our laboratory is a national competence center for the investigation of corrosion failure cases and the development of corrosion prevention strategies. Since the root cause of a material failure is often of combined chemical and mecanical nature, we combine our profound knowledge on corrosion mechanisms with long-term experiences in the fields of fractography, metallography and microstructural analysis of different types of metallic materials and their assemblies. On this basis, we offer high-end services to reveal the root cause of corrosion failure in the following domains:

• Civil Engineering: Buildings (supporting structures), Bridges (tension cables, reinforced concrete), Tunnels (supporting structures, operating infrastructures)
• Steel construction / Architecture: Ceilings, facades (anchoring elements), Balconies, terraces (steel constructions), indoor swimming pools (suspended ceilings, technical installations), windows (mounts)
• Mechanical engineering / Plants: Machine components (bearings, shafts, gears, etc.), Cranes (ropes), Plants (manufacturing facilities)
• Building technologies: Heating units, heat-exchangers, water-supply, air conditioning facilities, elevators
• Transportation: Railways, aviation, cable cars
• Industrial Products, Packaging

As a final outcome, we advise measures to prevent similar recurrent failures, damages and/or losses.

Your contacts: Dr. Markus Faller, Dr. Martin Tuchschmid, Martin Sauder

CORROSION TESTS

Corrosion tests are widely used to evaluate corrosion resistance of metallic components and surface coatings under realistic operation conditions. We offer a broad range of standardized corrosion and electrochemical tests both in environmental chambers and in the field, including:

• Test with condensation-water atmosphere according to EN ISO 6270-1 and 6270-2.
• Test with sulphur dioxide with condensation according to EN ISO 6988.
• Salt spray test (neutral solution) according to EN ISO 9227.
• Field corrosion tests at different corrosive test sites in Switzerland according to EN ISO 8565.
• Immersion test according to DIN 50 905 (part 1 to 4).
• Corrosion test for engine coolants according to ASTM D1384.
• Determination of rust-prevention characteristics of lubricating greases (EMCOR-Test) according to DIN 51 802 or ISO 11007.
• Standardized electrochemical tests according to DIN 50 918 and DIN 50 919.
• Test of copper alloys for stress corrosion cracking according to DIN 50 916 (part 1 and 2) and EN ISO 196.
• Determination of intergranular attack of stainless steels according to ASTM A262 and EN ISO 3651 (part 1 and 2).
• Determination of dezincification resistance of copper alloys according to ISO 6509.

If specific corrosion conditions are not covered by our standardized corrosion tests, we can design corrosion tests for your specialized applications.

Your contact: Dr. Markus Faller

LOCAL ELECTROCHEMICAL ANALYSIS BY MICRO-CAPILLARY TECHNIQUES

We offer unique and state-of-the-art local electrochemical characterizations of the surface reactivity and chemical durability of high-performance materials, coatings and technological components, as applied in civil engineering, medical implants, automotive industry, aviation, machine tooling, power generation, packaging, watches, microelectronics and sensing devices. To this end, in-house developed micro- and nano-capillary setups are used, which can be operated in (aggressive) liquid environments, as well as in defined gas mixtures at elevated temperatures (up to 1200ºC) on a local scale down to the nanometer range. Such localized electrochemical characterizations at selected heterogeneities on the material’s surface can be combined with ex-situ investigations of the surface and bulk microstructure of the material by conventional analytical techniques (e.g. SEM/EDX, XRD, XPS, AES, Impedance Spectroscopy and environmental AFM).

The principle of the electrochemical capillary technique consists of a tapered glass micro-capillary (with a ground tip diameter in the range of 0.2 - 1000 µm), which acts as a miniaturized electrochemical cell. The micro-capillary electrochemical cell can be positioned at selected locations on a solid surface with the help of an optical microscopic system. Since the electrolyte is directly inside the thin-walled capillary tip, the exposed (analysis) area is approximately equal to the contact area of the capillary tip on the material’s surface. To enable the detection of initial reaction stages at such a local scale, specially modified high-resolution potentiostats with a current detection limit as high as 20 fA are used. Modified micro-capillary setups allow local electrochemical measurements in liquids and gas mixtures at elevated temperatures with applied mechanical stress, additional friction or with electrolyte flow. These capillary electrochemical sensing techniques have been successfully applied to determine, e.g.

• the role of microstructural heterogeneities (e.g. precipitates, impurities, grain boundaries, micro-cracks, pores) on the reactivity and degradability of high-performance materials and coating systems.

• the chemical stability and biocompatibility of medical implants in bio-environments with simultaneous monitoring of local ionic dissolution processes.

• the altering behavior (deterioration or degradation) of the functional properties of electronic devices and sensors.

Your contacts: Dr. Thomas Suter, Dr. Patrik Schmutz.

DIFFERENTIAL SCANNING CALORIMETRY / DIFFERENTIAL THERMAL ANALYSIS (DSC/DTA)

Differential Scanning Calorimetry (DSC) is one of the most frequently employed Thermal Analysis methods. It can be used to analyse nearly all energetic effects occurring in a solid or liquid during thermal treatment (e.g. phase transformation enthalpies, grain growth, solidus and liquidus temperatures) . The NETZSCH DSC 404 C Pegasus® operates according to the heat flux principle. Using this method, a sample and a reference are subjected to a controlled temperature program (heating, cooling or isothermal within the temperature range from RT – 1500°C). The actual measured properties are the temperature of the sample and the temperature difference between sample and reference.

Your contact: Christian Leinenbach

HIGH SPEED IMAGING

For the detailed analysis of transient events, our laboratory provides a high speed camera. The camera (model HG-100K by Readlake) allows a recording speed up to 100.000 frames per second (fps) at reduced resolution (see manual). At the maximum resolution of 1504 x 1128 pixels, the camera provides a maximum recording speed of 1000 fps. With its fast electronic shutter, the camera allows to eliminate motion blurr and its robust design withstands accelerations up to 100 g. The model has been successfully used to:

• Investigate the fracture behavior in quasistatic and cyclic loading experiments.
• Monitor brazing and welding processes in real-time.
• Investigate image correlations to characterize the cyclic deformation behavior of brazed steel joints.
• Capture fast motions in sports.

The camera can be rent with an operator.

Your contact: Christoph Kenel

SCANNING ELECTRON MICROSCOPE (SEM) WITH EXTRA-LARGE SPECIMEN CHAMBER

Our Hitachi S-3700N SEM is designed to fill the gap between conventional optical microscopes (as available at e.g. the Empa User Lab Metallography) and high-resolution scanning electron microscopes (as available at the Empa Electron Microscopy Center). With its large analysis chamber, relatively large specimens and material components can be investigated (max. diameter 300 mm / max. height 110 mm). At the same time, the sample stage can hold specimens with a load of up to about 5 kg. It is equipped with the following detector systems for microstructural and compositional analysis:

• Secondary Electron Detector for investigation of topographical and morphological surface features with an ultimate lateral resolution down to about 5-10 nm (at 30 keV).
• 4+1 Quadrant Backscattered Electron Detector for simultaneous imaging of Z-Contrast and Topological features (3D-BSE).
• Up to date EDX Detector for elemental analysis including high-resolution phase mapping.

The SEM system is especially suited to investigate (large) fracture surfaces and/or heavy material components, as well as nonconductive materials (employing the systems' variable pressure function). If large or heavy samples or material components have to be investigated, without the need for extremely high lateral resolution and/or (ultra) high vacuum conditions, our SEM Operators are glad to help you out.

Your contact: Martin Sauder

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Affiliation

Empa - Materials Science & Technology
Laboratory for Joining Technologies & Corrosion
Ueberlandstrasse 129
8600 Duebendorf
Switzerland

How to get to the lab

Your contacts

Dr. Lars P.H. Jeurgens, Laboratory Head

Dr. Patrik Schmutz, Deputy

Claudia Frey, Assistant

Our team
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