Slip Deformation Analysis Based on Full Constraints Model for α-Titanium Alloy at Low Temperature

Abstract

The effects of restricted slip conditions on both the Taylor factor and plastic work rate under the condition of tensile yielding have been analyzed in -titanium alloys at low temperatures, using the full constraints model. The role of secondary slip systems, i.e., the hai basal slip and hc þ ai pyramidal slip, was clarified, when the hai prismatic slip was dominant. Although no influence of secondary slip conditions on the Taylor factor was detected, the plastic work rate was sensitive to the operating secondary slip systems. When the basal system was chosen as the secondary slip system, the plastic work rate increased in all tensile axes, especially around h0001i. In addition, no basal slip operation decreased the plastic strain energy. The plastic work rate was the highest along the h0001i tensile axis, and the operation of the hc þ ai pyramidal slip was necessary to achieve plastic deformation along c axis. High elastic strain energy, therefore, must accumulate to a high level around h0001i, because the pyramidal slip is hardly active owing to its very high critical resolved shear stress.

Simulating recrystallization in titanium using the phase field method

“…For titanium, M T was taken to be 2.5 according to Ref. [18]. Compression of titanium reduced one dimension of the sample by 20%, corresponding to an applied stress of 582 MPa [11].…”

Fractographical Analyses of Crack Initiation Site in High-cycle Fatigue for Ti–Fe–O Alloy at Low Temperature

“…3) Slip deformation analysis based on full constraints model by Taylor theory was suggested that internal stress in α grain was developed on the normal to (0001) and hardly relaxed. 7) The accumulated tensile stress along [0001] may be responsible for initial microcracking and its opening in the hard grain. Not only the microstructure and α grain size but also texture or macrozone (microtexture), therefore, strongly affect the subsurface fatigue crack initiation.…”

Effect of Si content on fatigue fracture behavior of hot-rolled high-silicon steels

“…The subsurface fatigue crack generation in titanium alloys (hcp) and austenitic steels (fcc), which has been commonly reported in high-cycle regime and at low temperature, [2,3] is closely related with heterogeneous deformation due to the restriction of slip systems. [4,5] Si addition in steel causes the restriction to {110} <111> primary slips, especially over 3.8 mass% Si content at room temperature. [6] The deformation and fatigue fracture behavior in Si steels depend on their Si content and are highly reflected on their crystal orientation and microstructure.…”