PSI - Issue 19

Motoki Nakane et al. / Procedia Structural Integrity 19 (2019) 284–293 Author name / Structural Integrity Procedia 00 (2019) 000–000

288

5

(a-1) Direction parallel to axis (Type 1)

(a-2) Direction perpendicular to axis (Type 1)

(b-1) Direction parallel to axis (Type2)

(b-2) Direction perpendicular to axis (Type 2)

(c-1) Direction parallel to axis (Emery)

(c-2) Direction perpendicular to axis (Emery)

Fig. 3 Example of surface profile of grinding and emery polishing specimens.

Table 4. Maximum roughness height. Grinding type

R z (  m)

Measurement direction to axis

(Grinding scratch direction to axis)

Parallel

5.4

Type 1 ( Parallel)

Perpendicular

10.6

Parallel

9.9 7.3 0.8 0.6

Type 2 (Perpendicular)

Perpendicular

Parallel

Emery polishing

Perpendicular

Fig. 4 Outline of fatigue test.

3. Test results 3.1. Fatigue test results

Fatigue test results of SUS316L plate are shown in Fig. 5. In high cycle regime, fatigue strengths of Type 1 and Type 3 grinding finish specimen are almost same as fatigue strength of emery polished specimen. On the other hand, fatigue strength of Type 2 specimen whose grinding scratch direction is perpendicular to cyclic loading direction is much lower than that of emery polishing specimen.