材料科学与工程导论双语课件教学课件 ppt 作者 陈克正 王玮 刘春延 等编Chapter 9.ppt

* * * * * π Phase diagram of Fe-Fe3C 卫星用自展天线 Deployable antenna Applications of Smart Materials Applications of Smart Materials Shape Memory Alloy Tube Joints Applications of Smart Materials 自膨胀血管支架 Self-expanding Intravascular? Stents Applications of Smart Materials Economical Outlook $1 Billion dollar market 75% - Electro-ceramics 10% -Shape Memory Materials 10% - Magnetostrictive materials 5% - Active Fluids Thank You! QUST * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * 9.2 Nanotechnology and nanomaterials Richard P. FeynmanThe Nobel Prize in Physics 1965 In 1959 Richard Feynman delivered his now famous lecture, “There is Plenty of Room at the Bottom.” 1 atom STM (1981)——The first to see one atom Nobel Prize in Physics (1986) A scanning tunneling microscope (STM) is a powerful instrument for imaging surfaces at the atomic level. Its development in 1981 earned its inventors, Gerd Binnig and Heinrich Rohrer (at IBM Zürich), the Nobel Prize in Physics in 1986. For an STM, good resolution is considered to be 0.1?nm lateral resolution and 0.01?nm depth resolution. STM (1981)——The first to see one atom With this resolution, individual atoms within materials are routinely imaged and manipulated. The STM can be used not only in ultra high vacuum but also in air, water, and various other liquid or gas ambients, and at temperatures ranging from near zero Kelvin to a few hundred degrees Celsius. STM (1981)——The first to see one atom The STM is based on the concept of quantum tunneling. When a conducting tip is brought very near to the surface to be examined, a bias (voltage difference) applied between the two can allow electrons to tunnel through the vacuum between them. The resulting tunneling current is a function of tip position, applied voltage, and the local density of states (LDOS) of the sample. STM (1981)——The first to see one atom Information is acquired by monitoring the current as the tips position scans across the surface, and is usually d