PSI - Issue 39

Keke Tang et al. / Procedia Structural Integrity 39 (2022) 387–392 Author name / Structural Integrity Procedia 00 (2021) 000–000

389

3

Tab.1 Ti-6Al-4V crystal plasticity model parameters (Han, 2016; Li et al., 2019; Han et al., 2017)

s τ /MPa

C11 /MPa

C12 /MPa

C44 /MPa

C13 /MPa

C33 /MPa

γ

0 h /MPa

0 τ /MPa

Parameter

n

Basal

Basal 420 Prism 420 Pyramidal 490

Basal 462 Prism 407 Pyramidal 539

631.2 Prism 436.2 Pyramidal 436.2

0.001

15

162400

9200

6900

180700

49700

α （ HCP ）

0.001

15

333

366

100

13500

11300

54900

-

-

β （ BCC ）

3. Tuning lamellar structure distribution The main purpose of the present work is to investigate the effect of lamellar structure distribution around elliptical notches with various sizes. Therefore, the employed strategy here is to formulate three groups of 9 cases. Aspect ratio is defined as the ratio between a and b as shown in Fig.2. For the designated size of elliptical notch, three case scenarios are studied. Considering composition of lamellar structure in RVE models are stipulated to be 34%, location of lamellar structures in three bimodal RVEs are varied. The 9 cases are displayed in Fig.2. The size of elliptical notch is also varied as well as lamellar structure distribution. It shall be noted that radial and circular paths are outlined around elliptical notch in Fig. 2(c). Strain extraction is based on these line paths.

Fig.2 RVE models with different lamellar structure distribution and notch aspect ratios