PSI - Issue 14

Puneeth N et al. / Procedia Structural Integrity 14 (2019) 53–59 Author name / Structural Integrity Procedia 00 (2018) 000 – 000

57

5

Table 7: Mean S/N ratio for fracture toughness

Level

Wt. %

Stir speed(rpm)

Stir time(min)

1 2 3

35.55 36.58 35.14

35.12 36.01 36.14

34.45 35.68 37.14

Delta

1.44

1.02

2.69

σ y -----Yield Point E ----- Young’s Modulus in MPa K iC --- Fracture Toughness J iC ------ Fracture Toughness is determined for ductile value. S/N ratio -------- Signal to noise Ratio Wt. % ------ weight percentage

SEM Photographs were obtained from Scanning electron Microscope. Fig 2 shows SEM photographs of Unreinforced AL6082, B1 (3.wt. %), B4 (6.wt. %), B7 (9.wt. %) type MMC’s. B1, B4, B7 fig shows distribution of Al 2 O 3 and Al 2 SiO 5 particles. As the wt % of reinforcements, stir time increases the distribution also increases. In Fig 5 composite material of 9wt. % Al 2 O 3 in B7 shows good distribution of particles and low agglomeration compared to 6 wt. % in B4 showed in Fig 4. Fig 4 of B4 type indicates that the Alumina Particles have tendency to segregate and cluster at inter- dendritic phases which are bounded by eutectic silicon as shown in Fig 3.

Fig 2 Shows SEM photographs of B0 MMC Unreinforced Al 6082.

Fig 3 Shows SEM photographs of B1 MMC contain Al 6082 reinforced with 3 wt. % of Al 2 O 3 and 4 wt. % of Al 2 SiO 5