Table 1 Overview of the group classification
Group | Control group | Length group | Diameter group |
|---|---|---|---|
Specimens | 18 specimens | 19 specimens | 22 specimens |
feature | Two identical springs | Different coil numbers (n1 = 4, n2 = 6) | Different coil radius (Δρ = 0.15 mm) |
Group | Control group | Length group | Diameter group |
|---|---|---|---|
Specimens | 18 specimens | 19 specimens | 22 specimens |
feature | Two identical springs | Different coil numbers (n1 = 4, n2 = 6) | Different coil radius (Δρ = 0.15 mm) |