| Particle Shape Descriptor | Cycles (Millions) | ||||||
|---|---|---|---|---|---|---|---|
| 0 | 0.5 | 2.5 | 5 | 6.25 | 7.5† | 10† | |
| Equivalent Circle Diameter(µm) | 1.22 (0.74) | 1.34 (0.92) | 1.55 (1.51) | 1.36 (0.89) | 1.17 (1.21) | 1.69 (3.62) | 1.04 (1.75) |
| Aspect Ratio | 1.45 (0.32) | 1.45 (0.34) | 1.54 (0.46) | 1.51 (0.43) | 1.42 (0.45) | 1.33 (0.22) | 1.35 (0.26) |
| Elongation | 1.74 (0.61) | 1.73 (0.63) | 1.93 (0.81) | 1.85 (0.88) | 1.63 (0.78) | 1.51 (0.45) | 1.51 (0.51) |
| Roundness | 0.74 (0.13) | 0.75 (0.13) | 0.71 (0.15) | 0.72 (0.14) | 0.82 (0.16) | 0.83 (0.13) | 0.83 (0.13) |
| Form Factor | 0.88 (0.07) | 0.88 (0.08) | 0.85 (0.10) | 0.87 (0.09) | 0.92 (0.09) | 0.93 (0.07) | 0.93 (0.08) |
Mean particle shape characteristics as defined by ASTM F1877 using SEM visual inspection. Particle shape descriptors in cycle time points denoted with an “†” were significantly different than the rest (P < .05). Values in parentheses denote one standard deviation.