Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Coating detachment finally understood

21.10.2003


In Friday’s edition of Applied Physics, TU Delft researchers will publish an article on how coatings are made and why they so often let go. “Finally, after 30 years, we know exactly what happens,” says Dr. Guido Janssen, materials expert at TU Delft and first author of the article to be printed in the prestigious American journal. Together with his colleagues at the Netherlands Institute for Metals Research (NIMR), he has brought the coating of very small components one step closer.



Taps, valves in a diesel motor or electrical components, many objects are coated. These thin layers can provide a certain visual enhancements, such as a reflective surface. They can also protect the coated material from being damaged. Janssen: “The problem is that in some cases, these coatings start to detach from the base material. The tap becomes ugly and the diesel valve is damaged, causing the engine to run less efficiently.”

The delamination of coatings is caused by tension forces within in the coatings. The atoms in the coating exert ‘pulling’ forces on one another, thereby finally pulling each other off the base material. Janssen: “This is a large problem within the mechatronics (mechanics combined with electronics) field, where the thickness of the coating often accounts for 10% of the total material thickness. The same tension is responsible for causing electronic chips to warp, and is it one of the that make it difficult to continuously develop more complex chips.”


Currently, the tension is combated by bombarding the coating with ions. The ions force the metal atoms aside slightly, exerting a pressure force that works against the tension force. The latest research done by Janssen and his colleagues shows that, contrary what has always been thought, the tension in the these coatings is not homogeneous. The tension at the top of the coating is higher than that at the bottom. Janssen: “ Now, after 30 years, we can see that ion bombardment does have an effect, but that one should use a large dose at the beginning and much smaller doses later on. This is just the opposite of current practice.” According to the Delft researchers, it may now be possible to apply a coating to, for example, very small switches for use in mechatronic systems, with out causing the switch to warp. Janssen: “ A real step forward.”

Maarten van der Sanden | alfa
Further information:
http://www.tudelft.nl

More articles from Process Engineering:

nachricht Intelligent wheelchairs, predictive prostheses
20.12.2017 | Fraunhofer-Institut für Produktionstechnik und Automatisierung IPA

nachricht Jelly with memory – predicting the leveling of com-mercial paints
15.12.2017 | Fraunhofer-Institut für Produktionstechnik und Automatisierung IPA

All articles from Process Engineering >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Attoseconds break into atomic interior

A newly developed laser technology has enabled physicists in the Laboratory for Attosecond Physics (jointly run by LMU Munich and the Max Planck Institute of Quantum Optics) to generate attosecond bursts of high-energy photons of unprecedented intensity. This has made it possible to observe the interaction of multiple photons in a single such pulse with electrons in the inner orbital shell of an atom.

In order to observe the ultrafast electron motion in the inner shells of atoms with short light pulses, the pulses must not only be ultrashort, but very...

Im Focus: Good vibrations feel the force

A group of researchers led by Andrea Cavalleri at the Max Planck Institute for Structure and Dynamics of Matter (MPSD) in Hamburg has demonstrated a new method enabling precise measurements of the interatomic forces that hold crystalline solids together. The paper Probing the Interatomic Potential of Solids by Strong-Field Nonlinear Phononics, published online in Nature, explains how a terahertz-frequency laser pulse can drive very large deformations of the crystal.

By measuring the highly unusual atomic trajectories under extreme electromagnetic transients, the MPSD group could reconstruct how rigid the atomic bonds are...

Im Focus: Developing reliable quantum computers

International research team makes important step on the path to solving certification problems

Quantum computers may one day solve algorithmic problems which even the biggest supercomputers today can’t manage. But how do you test a quantum computer to...

Im Focus: In best circles: First integrated circuit from self-assembled polymer

For the first time, a team of researchers at the Max-Planck Institute (MPI) for Polymer Research in Mainz, Germany, has succeeded in making an integrated circuit (IC) from just a monolayer of a semiconducting polymer via a bottom-up, self-assembly approach.

In the self-assembly process, the semiconducting polymer arranges itself into an ordered monolayer in a transistor. The transistors are binary switches used...

Im Focus: Demonstration of a single molecule piezoelectric effect

Breakthrough provides a new concept of the design of molecular motors, sensors and electricity generators at nanoscale

Researchers from the Institute of Organic Chemistry and Biochemistry of the CAS (IOCB Prague), Institute of Physics of the CAS (IP CAS) and Palacký University...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

2nd International Conference on High Temperature Shape Memory Alloys (HTSMAs)

15.02.2018 | Event News

Aachen DC Grid Summit 2018

13.02.2018 | Event News

How Global Climate Policy Can Learn from the Energy Transition

12.02.2018 | Event News

 
Latest News

Basque researchers turn light upside down

23.02.2018 | Physics and Astronomy

Finnish research group discovers a new immune system regulator

23.02.2018 | Health and Medicine

Attoseconds break into atomic interior

23.02.2018 | Physics and Astronomy

VideoLinks
Science & Research
Overview of more VideoLinks >>>