University of Helsinki - Research news
New solutions to problems with diamond coatings
A new diamond coating forms a hard, non-stick surface.
Week 45/ 2006
Best known as sparkling gems, diamonds are the hardest material known to man and very useful in a variety of applications that require hard-wearing, corrosion-resistant coatings.
Esa Alakoski, M.Sc., who has recently finished his doctoral dissertation on the properties of diamond-like materials, works in a research group at Orton Research Institute and the University of Helsinki, focusing on the development of thick diamond coatings for industrial and medical purposes.
"For years, people have tried to find a solution to the high internal stress of diamond coatings which causes problems with the attachment of thick diamond-coating surfaces. This is why practical applications have been few and far between," Alakoski says.
Now, however, the research group has found the answer in a new high-energy plasma technology.
"Thanks to this new technology, future diamond coatings can be tens or even hundreds of times thicker than today," he says.
According to Alakoski, the new technology will be commercially available in the next 5 - 10 years.
"For instance, tests run on an artificial hip simulator show that the abrasion and corrosion of the joint can be reduced to one millionth compared to the materials currently used," he says.
In addition to solving the attachment problem, the research group has managed to develop an entirely new coating: a diamond-polymer hybrid, which combines the exceptional mechanical qualities of the diamond with the non-stick properties of Teflon and silicone rubber.
The new hybrid coating has already broken one world record: drops of water start moving on a surface tilted at an angle of just 0.15 degree. This is the first time water has been seen to begin to move at an angle of less than 1 degree.
Applications for the new coating material include plastic moulds and artificial cardiac valves.
Text and foto: Simo Salmela
Translation: Valtasana Oy
