PSI - Issue 13

Kejin Zhang et al. / Procedia Structural Integrity 13 (2018) 1047–1052 Kejin ZHANG / Structural Integrity Proc d a 00 ) 00 0 0

1049 3

⌀ 10

31

40

70

200

5

Fig. 1. Schematic diagram of the specimen.

(a)

Shear affected zone (SAZ)

Punching

Punch

Sheet metal

Die

Die clearance

(b)

hole

Tensile Test

Fracture surface observation

Fig. 2. Schematic diagrams of (a) punching process (b) failure surface observation.

(a)

(b) Fig. 3. Tensile test results for (a) honed specimens; (b) punched specimens.

Figure 4 shows pictures of the punched specimens at a stroke displacement of 3.85 mm. The PH6 and PH8 specimen showed clear necking behavior around the stress concentration area compared with other steels [Hamada et al. (2018b)]. The PH8 punched specimen showed severe necking at the minimum cross-section of the specimen.