List of questions

1. Is there a high fatigue resistance material with low density suitable for AM-manufacturing of robot parts?

When designing robots, fatigue and stiffness properties are of vital importance.
One candidate is composites, e.g. epoxy/carbon fiber. However, in this AIMday discussion we would like to focus on metal solutions using Additive manufacturing (AM). AM opens up new possibilities when it comes to light weight design in general, for instance by using lattice structures, but e.g. the fatigue properties are often limited. This is partly due to the microstructure and surface roughness of the as-grown AM parts. The question is if it is possible to find a material optimized for AM and in combination with the proper AM process and post process, obtain superior material properties to a reasonable cost?

What makes 3D-printed cellulose different?

Additive manufacturing technologies are being considered for a number of materials. the bio-based materials are of interest, in particular the cellulose-based ones.
What are the structural- mechanical characteristics of 3D-printed cellulose?
What makes 3D-printed cellulose different?
Is it possible to characterize in a quantitative way the structure from a microscopic point of view?

Can optical fiber carry electricity?

Background
Power-over-fiber, or PoF, is a technology in which a fiber optic cable carries optical power, which is used as an energy source rather than, or as well as, carrying data. In 2012, scientists from Sandia National Laboratories in New Mexico invented one of the earliest power-over-fiber systems, using laser diodes on one end of the cable and a miniature photovoltaic cell on the other end. However, the scientists acknowledged the system’s limitations, saying that it could only power the fiber’s internal electronics.
A lot of research and interest there is in the development of laser systems for the power conversion to increase efficiency, costs and safety.
There are nowadays few patents and companies popping up with commercial solutions for low power applications, but there is a trend in going up in power.
A lot of applications can be thought also in the automotive and aeronautical industries.


Question:
Please, what is your opinion about the development of optical fibers for power transmission? Which are your opinions on the developments needs and dynamics?
Which are the main technical and economic problems in their manufacturing and in the materials engineering?

How to determine the heat transfer in the powder as function of pressure in the Cold Isostatic Press?

Ereasteel Kloster produces tool steels from powder that is filled in capsules and solidified in a stepwise process.
1. The capsule is evacuated and backfilled with 1 atm Nitrogen.
2. Cold isostatic pressed (CIP) at high pressure to increase the relative density.
3. Pre-heated in furnace to 1130C for 18 hours.
4. Hot isostatic pressed (HIP) at 1150C at 1000Bar for 1 hour to full density.
The heat transfer in the powder is very low due to the small contact area between the powder particles. The contact area depends on the CIP pressure. The time to reach full temperature in the center of the capsule depends on the CIP pressure.

• What would be the best way to deposit a very hard optical thin film layer coating onto a temperature sensitive substrate?

Chalcogenides is a group of infrared transmitting materials with quite low transition temperatures. This makes them very difficult to coat with abrasion resistant coatings that often require a high substrate temperatures. Are there suitable (abrasion resistant, IR transmitting) materials that can be evaporated at low substrate temperatures or are there other techniques for cold coating that doesn’t heat up the substrate to much during the process?

Can a nanostructured surface both anti reflective and self cleaning?

Films for energy harvesting, protective or active, are becoming very important in the field. How does dirt affect the transmission, how can we keep it clean, without escalating cost?

How can we test and prove biocompatability using different materials and nanostructures?

Biocompatability is very important in particular for implants both long and short term. Which materials and nanostructures work the best?

What happens to argon pores in additively manufactured components after Hot Isostatic Pressing?

There is a great deal of discussion regarding where Argon end up in the metal matrix and TIP (pore regrowth) is considered an issue in the AM industry. MAterials or particular interest are Ti6Al4V and Nickel alloys such as A718, A738 etc.

How does pressure affect phase transformations include nucleation and growth during heat treatment cycles under hot isotatic pressures up to 200MPa?

TTT/Phase transformation diagrams are in 2 dimensions in all literature. Today high pressure heat treatment is beng introduced for castings and 3D printed metals, where quenching cycles are carried out under pressures up to 170MPa. Development of phase transformation diagrams in 3 dimensions (T, t, P) is needed for indstrial implementation.

What future possibilities are there in materials or surfaces with regards to absorption/dissipation of acoustical energy from the air?

Traditional materials used in this field for noise control are porous materials like foams or compressed fibers (nonwovens, glass or mineral wool, polymer fiber wools). New technologies offers many more possibilities also in large scale volumes.

1. How can properties of martensitic boron steel be controlled to achieve a specific combination strength/ductility?

We use martensitic boron steel in beams for load transfer and certain energy absorption in passenger cages. We have tried with locally controlled cooling integrated soft zones in drill bars, evaluated chemistry and alternative cooling processes and mechanical properties. We want to know if properties could be controlled or be tailored for example with TTT curves or alloy composition.
We need e g sections with high ductility close to sections with high strength and or higher thickness. The question is if it is possible and how to combine sections of high strength and high ductility rel close to each other in a component, by e g chemical composition and / or heating / cooling

2. How to design and join structures of a mixed material (e.g. aluminum and steel) of components with different thermal properties?

Mixed metal structures are used in the chassis e.g. aluminum beams on steel panels (or vice versa). We have already carried out simulation and samples of thermally induced deformations in generic mixed metal compounds and chassis parts. A specific problem is how to minimize the thermally induced stress and deformations in an aluminum/steel joint at a temperature of 200 C. We would also need to generate data as a function of temperature (20-200 C) for heat transfer, heat conductivity and strength of aluminum/steel mixed material.
The thermal dilataton causes deformations and stresses that we need to minimize by right material combinations and joint configuration, and also develop material models with the correct material data as function of temperature. We are lacking e g data on heat treansfer, heat dissipation and strength as function of temperature from 20 – 200 C for aluminum sheet and cast materials

3. How to predict the properties of a composite structure assembled with a metal structure?

The area of application is very broad from the development of processes for joining composites to other material to the properties of the assembled component. We have already carried out several designs and tests of diverse composite structures. A specific composite we would like to study is CRP (Carbon fiber reinforced polymer) composites.
How to virtually predict deformation and load behavior of a mixmaterial structure including both CFRP and metals joined together