论文部分内容阅读
HRTEM观察到45钢冲击磨损表面的非晶-纳米晶混合组织由几个纳米的晶粒和非晶组成,而沿着裂纹表面有非晶呈带状分布。热力学计算表明,在冲击载荷下可能存在一种新的非晶形成机理,非晶可由纳米晶粒转化而来,而裂纹表面是非晶形成的优先位置,与观察结果相符,且界面能在非晶转变中起到主要作用。计算结果还表明材料内部也可形成非晶,但阻力较大。而不经由纳米晶直接由高密度位错区形成非晶则非常困难。
HRTEM observed 45 impacted wear surface of the amorphous - nanocrystalline mixed tissue composed of several nano-grains and amorphous composition, and along the crack surface amorphous ribbon distribution. Thermodynamic calculations show that there may be a new mechanism of amorphous formation under impact loading. The amorphous phase can be transformed from nanocrystalline grains, and the cracked surface is the preferential position of amorphous formation, which agrees with the observation and the interface can be in the amorphous Change plays a major role. The calculation results also show that the material can also be formed within the amorphous, but greater resistance. It is very difficult to form amorphous directly from high-density dislocation regions without nanocrystals.