China scientists develop coating that can keep knives sharp for 100 times longer
Chinese scientists say they have developed a coating that keeps a knife sharp 100 times longer than one without the material.
The anti-wear coating was developed by a team headed by Huang Feng, a professor at the Chinese Academy of Sciences' Ningbo Institute of Material Technology and Engineering.
Huang said the film could be applied to more than just kitchen knives - it could also be used in manufacturing, potentially increasing product lifespan and boosting the competiveness of heavy industry.
It takes 1,000 grindings, under the force of 10,000 times the atmospheric pressure, to wear off one layer of atoms of the anti-wear coating, the team says. "If applied to a kitchen knife, the lifespan of the knife may be extended beyond the life of its user," Huang told the South China Morning Post.
The coating is made of various nitrogenised metals such as chrome and vanadium. It was a few micrometres thin and could be applied to the surface of almost any machine, Huang said.
The material could have applications in aviation and carmaking. Chinese manufacturers tend to use anti-corrosive coatings from Europe, especially Germany, to prolong the life of machines and maintain production line quality.
Huang hopes the material, which has been patented, will help improve the reputation of "made in China" products and help the country compete directly with Western technology.
But Yang Kai, an expert in the field of anti-corrosive materials at the Shanghai Institute of Ceramics under the Chinese Academy of Sciences, said that while Huang's results were impressive, the material would need to be proven in the working environment.
Many variables, such as temperature and stress, could affect the performance of anti-corrosive material, and these factors could not all be replicated in a laboratory setting, said Yang, who has developed coatings for China's aerospace industry.
"But the reported result is impressive indeed," he said. "Their work is worth following up."
Huang said he had tried to find a Chinese factory that would use the coating, but it was not easy.
Most of the manufacturers he spoke to were reluctant to make the investment in coating their machinery and they often wanted to see immediate results.
It could take as long as a year to coat the machinery in a factory, Huang said. This period may be considered relatively short elsewhere, but few Chinese entrepreneurs are willing to see their production lines suspended during the process.
If the government provided an "anti-corrosive" subsidy and factory owners could be convinced of the added value, in a decade's time China may stand beside Germany as a producer of top-quality cutlery and anti-corrosive material, he said.