论文部分内容阅读
研究了Ｔｉ－６．５Ａｌ－３．５Ｍｏ－１．５Ｚｒ－０．３Ｓｉ合金细观结构对裂纹扩展特性的影响。发现当△Ｋ值小于ｄａ／ｄＮ－△Ｋ曲线上转折点处△Ｋ值时，合金出现解理断裂，表明转折点是解理断裂向条纹机制断裂的过渡；大量试验又进而证明，解理断裂与裂尖塑性区大小和裂纹穿过的晶粒或晶域尺寸有关。由此，作者提出了钛合金在裂纹扩展过程中形成解理断裂的一种新的断裂机制。
The effect of mesostructures on crack propagation properties of Ti-6.5Al-3.5Mo-1.5Zr-0.3Si alloy was studied. It is found that when the value of △ K is less than △ K at the turning point on da / dN- △ K curve, the alloy shows cleavage fracture, indicating that the turning point is the transition from cleavage fracture to stripe mechanism fracture. A large number of experiments further prove that cleavage fracture and The size of the crack tip plastic zone is related to the size of the grain or crystal grain through which the crack passes. As a result, the authors propose a new fracture mechanism for the formation of cleavage fractures in the titanium alloy during crack propagation.