TC21 titanium alloy,as an important metal to fabricate the aircraft structural components,has attracted great attentions recently.A TC21 titanium alloy with widmanst?tten structure was isothermally compressed.Based on...TC21 titanium alloy,as an important metal to fabricate the aircraft structural components,has attracted great attentions recently.A TC21 titanium alloy with widmanst?tten structure was isothermally compressed.Based on the microstructure observation,the evolution of initialβgrain,Grain Boundaryαphase(α;),lamellar a and interlayeredβwas systematically investigated.The results showed that,with the increasing of height reduction,theα;underwent an evolution process from bending/kinking to breaking inducing the corresponding blurring of initial coarse b grain outline.Meanwhile,a significant phase transformation from a to b took place at the terminations of brokenα;.The evolution of lamellarαand interlayeredβin the colony was closely related to their deformation compatibility.In the a colony,the interlayered b experienced a larger deformation amount than lamellarα.The higher distortion energy promoted the occurrence of Dynamic Recovery(DRV)and Dynamic Recrystallization(DRX)to generate many Low Angle Boundaries(LABs)and High Angle Boundaries(HABs)in interlayered b,which induced an apparent grain refinement of b phase.On the contrary,the lower distortion energy and low deformation temperature suppressed the occurrence of DRV/DRX and restrained the globularization of lamellarα.Furthermore,the microstructure observation clearly revealed that the shearing separation mechanism dominated the evolution of the a phase from lamellar to short bar-like morphology.展开更多
基金supported by National Natural Science Foundation of China(No.51971046)Fundamental Research Funds for the Central Universities,China(No.2020CDJGFCL005)。
文摘TC21 titanium alloy,as an important metal to fabricate the aircraft structural components,has attracted great attentions recently.A TC21 titanium alloy with widmanst?tten structure was isothermally compressed.Based on the microstructure observation,the evolution of initialβgrain,Grain Boundaryαphase(α;),lamellar a and interlayeredβwas systematically investigated.The results showed that,with the increasing of height reduction,theα;underwent an evolution process from bending/kinking to breaking inducing the corresponding blurring of initial coarse b grain outline.Meanwhile,a significant phase transformation from a to b took place at the terminations of brokenα;.The evolution of lamellarαand interlayeredβin the colony was closely related to their deformation compatibility.In the a colony,the interlayered b experienced a larger deformation amount than lamellarα.The higher distortion energy promoted the occurrence of Dynamic Recovery(DRV)and Dynamic Recrystallization(DRX)to generate many Low Angle Boundaries(LABs)and High Angle Boundaries(HABs)in interlayered b,which induced an apparent grain refinement of b phase.On the contrary,the lower distortion energy and low deformation temperature suppressed the occurrence of DRV/DRX and restrained the globularization of lamellarα.Furthermore,the microstructure observation clearly revealed that the shearing separation mechanism dominated the evolution of the a phase from lamellar to short bar-like morphology.
