List of questions

What analyzing methods could be used to study contact erosion in sealed vacuum interrupters?

Vacuum interrupters (VI) have superior breaking performance in the medium voltage range and are extensively used in the power electrical network. It consists of fixed contact, moving contact and a metal arc shield mounted inside a ceramic vacuum chamber. The movable contact is connected to the control mechanism by stainless steel bellows. This enables the permanent sealing of the vacuum chamber so as to eliminate the possibility of leak.
In development tests, one challenge is to study the contact erosion without breaking the sealed vacuum. X-ray imaging has been used but because of the ceramic wall and the metallic shield the resolution is not the best and quantitative measures of contact erosion and surface roughness is difficult to obtain.

How does Upsalite work together with oils?

Upsalite is a material well known for its extreme ability to absorb water. ABB has a number of applications and technologies in which such functionality could be critical. Moreover we would like to have a deeper understanding and its potential for us.
Technical questions/issues
• Basic physical data for Upsalite.
• Upsalite as an electrical insulator?
• How does Upsalite work together with oils?
• Could it absorb moisture when immersed in oil?
• Can Upsalite be used as a filler in a polymer with retained properties?
• Can Upsalite accommodate large amounts of fluids other than water?
• Long-term stability of Upsalite?
• Temperature properties/stability of Upsalite?
• Release of water from Upsalite? How? How fast?
• Etc.

How can new technologies and materials become potential solutions for efficient water cleaning and/or desalination?

Shortage of clean water is quickly becoming a global problem. Only about 1% of earths total water reserve is actually potable and demand is increasing. Already, 500 million people live in places where water consumption is double the amount replenished by rain for the whole year. To meet future demands better management of existing fresh water and cheaper, more efficient methods of turning undrinkable water into pure H2O will be needed. In addition, water cleaning systems in US/Europe is becoming old (cf. electrical grids) and will soon need to be replaced, which opens up for new business opportunities. Key is here to increase flow rates, lower energy consumption and reduce cost.
ABB is a provider of automation solutions for water and wastewater treatment plants, with the overall target to minimize the considerable energy usage needed in the operation of these plants. We are interested in learning more about potential solutions for rapid water disinfection and/or desalination. Are there new materials or technologies that could efficiently and at a high throughput flow selectively remove e.g. bacteria, metallic species, ions (salt) or specific chemicals? What are the factors limiting rate in e.g. ion exchange filters or bacterial filters? Can electric/magnetic fields be used as alternatives or to enhance effects?

X-ray micro-tomography – can that be used to investigate the breakdown path in a mica-epoxy composite machine insulation structure?

For a long period of time, the use of mica impregnated with epoxy resin has been used as electrical insulation of stator coils in large rotating machines with a rated voltage above 1000 V.
The mica material, in the form of mica-paper, is wrapped around the coils in a tape format. For mechanical reasons, the mica-paper has to be reinforced with a glass carrier. The mica tape is applied in such a way that it overlaps the previously turn with 50%, i.e. the layers are applied ½-over lapped. In order to build up the final insulation thickness, several layers are placed on top of each other. The thickness of the mica-tape is around 0.15 mm and the final thickness is in the range of 2-3.5 mm, depending on the rated voltage for the machine. As a final step, the insulation is vacuum pressure impregnated (VPI) with an epoxy resin. In Fig 1, a schematic sketch of insulation structure are shown.


The use of mica gives a very good resistance toward partial discharges (PD) which occur in small voids in the insulation then a high voltage is applied across the insulation layer. However, despite the good PD-resistance of mica, ongoing PD’s will slowly deteriorate the insulation system and in the end lead to a final breakdown.
Even if this type of mica/epoxy insulation has been used for many decades, the actual breakdown mechanisms and breakdown path are not well understood. A widely spread hypothesis is that PD-activities in small voids will deteriorate the organic impregnation resin around the mica tape, whereas the inorganic PD-resistant mica paper will not be much affected. That means that the mica tape layers will act as barriers and the breakdown path will follow the polymeric resin layers on its way through the insulation, see Fig 2.


After the final breakdown, the material around the breakdown path will be burned away and no evidence of the original breakdown path can be found. However, with the use of micro-tomography, it could be possible to actually follow the growth of the breakdown path during electrical aging and verify the hypothesis described above. One of the benefits with the use of micro-tomography is that the electrical aging could be temporary stopped and the growth of the breakdown path could be investigated without destroying the insulation layer. After that the breakdown path has been checked, the electrical aging could continue until it is time for the next check. In that way, the growth of the breakdown path could be followed until the final breakdown of the insulation.
In the area of machine insulation, micro-tomography has been used by A. Contin et al. [1] for evaluation of the void content in a mica-epoxy structure, see pictures in Fig 3.

Is it possible to in-situ characterize the failure pattern in cellulose-based electrical insulation?

Cellulose-based material are commonly used as insulation in High Voltage applications. In general the cause of failure is exposition of the material to high electrical fields exceeding the limit of the material. However the strength value of the material can significantly vary within the same test piece. Failure occurs in a small area concentrated in a small area where local defects can arise due the internal arrangement of the material. The task is to investigate the pattern of electrical failure in-situ or before and after failure.
The goal is to define the influence of internal material topology, surface unevenness on the development of the failure.

How to characterize the deformation field area in insulation material subjected to large impulse forces?

Short circuit in electrical apparatuses can cause high compressive forces applied on insulation material. The forces are of impulse nature, i.e. very short rise times. As a result of the mechanical forces, the insulation material is largely deformed after a failure. In order to reduce the negative consequences of such deformation it would be an advantage to understand the structural changes occurring within the material.
The investigation should focus on the characterization of the deformation field in the area where the applied load. The characterization could also be extended by taking into account the effect of plasticizers (e.g. moisture)

How can cellulose fibres be surface-modified to improve mechanical or wetting properties of pressboard?

Pressboard is a cellulose based material which ABB is manufacturing for use as electrical insulation in power transformers. The pressboard material is machined in to different components and the porous structure of pressboard is impregnated with oil in its final function. The question is related to if the mechanical properties can be improved by e.g. chemical surface modification i.e. sol-gel technology, Atomic Layer Deposition or covalently grafting other chemical structures onto the cellulose fibre surface. Also, it is interesting to investigate the ability to hindering moisture absorption of the cellulose fibers material, which would influence the processing of the pressboard material.

How much knowledge do we have in Sweden when it comes to melting of chalcogenide materials?

We know that there is no production at all in Sweden today of such materials, but there might be knowledge somewhere in Sweden anyhow around how it is done. And maybe also what kind of equipment that is needed? After all, we have some kind of glass culture in Sweden since long back.

For visible range optics, plastic lenses are dominating the small camera market - is it possible to find a polymer material for molding IR-lenses with transmission in the 8 to 12 um spectral range.

”The holy grail” within IR-optics is to be able to mould a polymer material with desired transmission, as in the visible range. We know people have been looking into this, but we have never seen something close to a solution.

What differs USP Class VI o-rings to non Class VI o-rings in terms of composition, and how does it affect the properties of the o-ring?

Several years ago our company made a transition to USP Class VI for wetted plastics and O-ring material. This was made to provide a better product to our customers, what could this mean for the lifetime compared with materials without this standard. And are there other side effects such as shrinking or swelling effects over time compered to material without this standard.

All our wetted plastics and O-ring material conforms to the following standards.
Animal origin-free
EMA/410/01 CPMP
USP Class VI
CFR Part 177

Materials commonly used in our products.
EPDM: EthylenePropyleneDieneMonomer rubber
FEP: FluorinatedEthylenePropylene
PP: PolyPropylene
PMMA: PolyMethylMethAcrylate, family name for e.g Acrylic
PEEK: PolyEtherEtherKetone

How can we integrate pressure sensors in steel sheets for in-situ measurements of a high pressure water flow towards a surface?

Objectra has developed equipment to measure addhesion of preferably car paint. The aim now is to develope the method further by measuring, in-situ, the pressure at the surface when exposed to a high pressure water stream. Is it possible to efficiently integrate the sensors to map the pressure?

The method is supposed to simulate what happens when washing a car with high pressure water (water jet). The case with a car paint surface damaged by stone chips is of course of great interest.

What is the difference between conventional 316L and AM (3D-printing) 316L components?

We have seen by measuring the speed of sound in both those materials, that it is significantly higher in the conventional material. We wonder why?

How can Forsmark and Ångström laboratory collaborate around nuclear power?

We just generally wonder how we can interact with the Ångström laboratory around nuclear power?

What are the similarities and differences in the tribological behavior of stainless steel and titanium alloys?

We have interest in the tribological behaviour and differences in those two material. For example in a high load dry friction test, for the same conditions what are the differences in Heat, Materials Adhesion, Workpiece microstructure, Forces ...?

Is it possible for metallic ion, such as Mg2+ to be inocorporated in the passive film of a stainless steel in a corrosive environment

To be able to rank super grades of stainless steel grades for corrosion properties methodologies has been developed to use MgCl2 for higher boiling points. Researchers in US claim that magnesium can be incorporated in the passive film when exposed to saturated magnesium chloride. However, based on thermodynamic, a hugh amount of energy is required to incorporate the magnesium into a metal surface. The question is focussing on whether this is possible at all. Can this question be answered by surface analysis. More background in attached file /published at Eurocorr 2016 12 september.

Finns det någon analys- eller modelleringsmetod som kommer åt punktfrätning på rostfritt på ett bra sätt?

Punktfrätning är den dominerande korrosionsformen för passiverande metaller. Genom att följa ström/ laddning kan man uppskatta initerings- och repassiveringstiden till kortare än millisekund för den nanometertunna filmen. Storleken på nyligen initierade gropar kan ligga i området 0.1-1 µm. Den ideala analystekniken för att följa ett initieringsförlopp skulle alltså vara in situ, ha en bättre lateralupplösning än 100 nm och en bättre tidsupplösning än 1 ms. Finns den?

Följdfråga: Hur långt är det kvar tills man skulle kunna modellera växelverkan mellan kloridkluster, passivfilm, och underliggande metall? Skulle vara intressant att höra synpunkter från en initierad kvantkemist. En fungerande modell för "tid till initiering" av punktfrätning skulle vara av intresse, speciellt om man kan få den att gå mot oändligheten.

Vid borering fås ett hårt ytskikt i kombination med en låg friktionskoefficient och därmed en minskad tendens till kallsvetsning. Vad vet vi om boriders tribologiska egenskaper?

Det finns exempel på borider som blivit kantiga vid ökande härdtemperatur, varför?

How should "effective size" for martensitic and bainitic steel be evaluated?

I takt med att EBSD-tekniken (electron backscatter diffraction) har förfinats och snabbats upp har ”boundary engineering” blivit allt mer uppmärksammat som ett hjälpmedel till att försöka förstå hur slagsegheten beror av mikrostrukturen hos martensitiska- och bainitiska stål. Istället för att koncentrera sig på absolut kornstorlek koncentrerar man sig istället på relativa misorienteringen mellan kristaller. I sammanhanget utgår man från områden som omsluts och överskrider en på förhand angiven minsta relativ misorientering (vanligtvis 15°). För att kvantifiera dessa områden markeras gränserna manuellt på dator (enligt EBSD-mappen) och approximeras med en mjukvara från tredje part till ellipser. Vidare transformeras ellipsernas omkrets till ECD (ekvivalent cirkel diameter) vilket i sin tur utgör ”effective sizes”. Dessa presenteras normalt i form av histogram och man har kunnat visa att en finare ”effective size” ger upphov till en bättre slagseghet för bainitiska stål.

Är detta ett bra sätt att mäta ”effective size” på eller behöver fler aspekter tas i beaktning? Hur påverkar morfologin hos ingående paket (nålliknande, likaxliga etc.) resultaten och hur ska man ansätta detta?

What elements in the tool steel could be used to build a proective film?

In high pressure die casting of aluminum, thermal fatigue (or heat checking) commonly occurs on the tool. How does the aluminium affect the crack initiation?

Some tool manufactures preoxidize the tools and claim longer lifetime, thus the oxide film should have protective meassures.

How to avoid adhesion of AlSi or Zn from the work material surface treatment, on the tool steel in press hardening applications?

What is the difference between conventional 316L and AM (3D-printing) 316L components?

We have seen by measuring the speed of sound in both those materials, that it is significantly higher in the conventional material. We wonder why?

How can Forsmark and Ångström laboratory collaborate around nuclear power?

We just generally wonder how we can interact with the Ångström laboratory around nuclear power?