Issue 38

T. Inoue et alii, Frattura ed Integrità Strutturale, 38 (2016) 259-265; DOI: 10.3221/IGF-ESIS.38.35

Max. load

±50 kN ±50 mm

Max. stroke

Max. frequency under uniaxial loading Max. frequency under tri-axial loadings 5 Hz Table 1 : Specifications of planar tri-axial fatigue testing machine. 10 Hz

Test Specimen Two types of specimens made of SS400 were used as shown in Fig. 3. One was designed as a cylindrical projection on the center of the specimen as shown in Fig. 3 (b). The other was flat shaped as shown in Fig. 3 (c). The chemical composition and mechanical properties of SS400 are shown in Tabs. 2 and 3.

300

x

y

17.5

R30

R10

A’

0 deg.

300

A

27.5

R20

Arm

50 60

Chuck area

45 deg.

50

Unit : mm

90 deg.

(a) Top view.

 6

R10

R0.5

R200

7.5

A 16

A 16

A’

A’

1

1

1.6

R7.5

 21.9

 40

 40

Unit : mm

Unit : mm

(b) A-A’ cross section view of projection type.

(c) A-A’ cross section view of flat type.

Figure 3 : Test specimen.

C

Si

Mn

P

S

Fe

0.16

0.15 Bal. Table 2 : Chemical composition of SS400 in wt. %. 0.67 0.012 0.005

Tensile strength (MPa)

Yield stress (MPa)

Elongation (%)

434

277

32

Table 3 : Mechanical properties of SS400.

262