Figure 1: Optical micrographs of the microstructure of the STOA Ti-6Al-4V plate

Figure 2: Schematic illustration of (a) the FODed "K_b" bar used for high-cycle fatigue testing, and (b) the detail of the impact conditions

Figure 3: Schematic diagram of the high-velocity impact facility
 
 
      

Figure 4: Scanning electron micrographes of simulated damage sites. Impact-conditions: 3.2mm chrome-hardened steel sphere, normal impact (90º) at impact velocities of (a) 309 m/s and (b) 201 m/s

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Figure 5: Optical micrographes of cross-section of simulated damage-site. Impact-condition: 3.2 mm chrome-hardened steel sphere, normal impact (90º), at 309 m/s.
 

Figure 6: Optical micrographes of cross-section of simulated damage-site. Impact-condition: 3.2 mm chrome-hardened steel sphere, normal impact (90º), at 200 m/s.

Figure 7: Schematic of the damage zone beneath an FOD impact crater
 

Figure 8: Influence of impact-velocity on dimensions of the damage from a 3.2 mm chrome-hardened steel sphere under normal impact conditions