by Yang Jingzhong, Bao Yue
COPENHAGEN, Sept. 27 (Xinhua) -- New research by Danish and Chinese scientists could help revolutionize the way nanometals are understood and used in daily life.
The Danish-Chinese Center for Nanometals, founded in 2009, facilitates academic cooperation between Danish and Chinese scientists in the area of nanoscience and technology with a focus on metals.
It believes nanometals are an important research field with great potential benefit for individuals and society as it has many applications in industry.
"Research has shown that, when the interior structure of the metal is reduced to nanometer scale, not only can the properties of metals be improved but also completely new properties and behaviors may be achieved in these new materials," explained Dr. Grethe Winther, a key scientist and Danish coordinator at the center, in an interview with Xinhua.
All metals are composed of 'crystal grains' or regularly arranged structures of atoms. A metal is considered 'nanostructured' when the grain size within the metal is below a few hundredths of a nanometer, a unit measuring one millionth of a millimetre, or around 100,000 times thinner than a human hair. In an ordinary metal, the grain size is typically in the range of a few to hundreds of micrometers.
Moreover, nanometals respond in unexpected ways depending on how they are treated.
"Our common knowledge about metal is that it gets harder when it is deformed and on the other hand, it becomes softer by being heated up," Dr. Huang Xiaoxu, a senior scientist at the center, told Xinhua.
"However, we found that the nanostructured metals are softened by being deformed and hardened by annealing," he added.
Annealing refers to a heat treatment that changes the properties of a metal, such as its strength, hardness and ductility, by altering its microstructure.
