With the development of science and technology, there are more and more kinds of new alloys. Here are some main ones.
light alloys
Aluminum lithium alloy has the characteristics of high specific strength (breaking strength/density), high specific stiffness and low relative density. If it is used as a modern aircraft skin material, a large passenger aircraft can reduce the weight by 50 kg. Take Boeing 747 as an example. For every 1kg reduction, it can earn 2000 dollars a year. Titanium alloy is lighter than steel, corrosion resistant, nonmagnetic, and has high strength. It is an ideal material for aviation and naval ships.
Hydrogen storage alloy
Due to the limited reserves of oil and coal, and the environmental pollution caused by their use, especially the global oil crisis in the 1970s, hydrogen as a new clean fuel has become a research hotspot. In the process of hydrogen energy utilization, hydrogen storage and transportation is an important link. In 1969, Philips of the Netherlands developed LaNi5 hydrogen storage alloy, which can absorb and release a large amount of hydrogen reversibly. The density of hydrogen in its alloy hydride LaNi5H6 is equivalent to that of liquid hydrogen, about 1000 times that of hydrogen.
Hydrogen storage alloy is an alloy composed of two specific metals, one of which can absorb a large amount of hydrogen to form a stable hydride, while the other metal has a small affinity with hydrogen, but hydrogen is easy to move in it. Mg, Ca, Ti, Zr, Y and La belong to the first metal, while Fe, Co, Ni, Cr, Cu and Zn belong to the second metal. The former controls the amount of hydrogen stored, while the latter controls the reversibility of hydrogen released. Through the reasonable preparation of the two, the hydrogen absorption and desorption properties of the alloy can be adjusted to prepare an ideal hydrogen storage material that can reversibly absorb and release hydrogen at room temperature.
Superalloy
Nickel cobalt alloy can withstand the high temperature of 1200 ℃ and can be used for components of jet aircraft and gas turbines. Ni Co Fe non-magnetic heat-resistant alloy still has high strength and good toughness at 1200 ℃, which can be used for parts of space shuttles and control rods of atomic reactors. It is still the research direction in the future to find alloy materials that meet the requirements of high temperature resistance, long-term operation (more than 10000 h), corrosion resistance and high strength.
