Scientists have developed high - performance molybdenum alloys
With the support of the national natural science foundation and other projects, sun jun research group of xi 'an jiaotong university national key laboratory of metal material strength successfully developed the nano-structured dispersion reinforced molybdenum alloy material. The material has nano-enhanced rare earth oxide particles and ultrafine microstructure, and the tensile ductility is increased exponentially. The results were recently published online in the journal nature materials science.
According to the introduction, China's molybdenum reserves, production and consumption are ranked first in the world. Molybdenum is widely used in the production of various kinds of steel materials such as stainless steel. Molybdenum alloy has a broad application prospect in aerospace, machinery, metallurgy and other fields due to its excellent thermal conductivity and high temperature resistance.
However, due to the low temperature brittleness, low strength and poor ductility of molybdenum, the deep processing of molybdenum alloys is difficult and its application is greatly restricted. For many years, molybdenum industry in China mainly produces primary products of molybdenum. Therefore, the research and development of molybdenum alloy materials with better performance and higher added value is of great significance to the development of molybdenum industry in China.
Starting from the actual engineering requirements, sun jun's research group traced back to the difficulties of material preparation technology, revealed the characteristics and mechanism of size effect of toughening and toughening of grains and intra and boundary particles in rare earth oxide doped molybdenum alloy, established a quantitative analytical model of toughening and toughening, and proposed a new idea of toughening and toughening by nano doping.
Based on this, the researchers developed a molecular level preparation containing nano rare earth oxides doped liquid mixing molybdenum alloy, the key technologies to solve the nano rare earth oxides and the aggregation, uniform dispersion in molybdenum grain interior and grain boundary distribution and the high temperature stability of ultrafine nano crystal structure and so on three key problems restricting the development of the field. The strength, ductility and ductility of molybdenum alloys prepared by them are higher than those reported by world-class companies. Meanwhile, the plastic-brittle transition temperature is significantly reduced, and the high-temperature recrystallization temperature, high-temperature strength and tensile ductility of the alloys are significantly increased.
