A.4B.3C.1D.2
A.45°~60° B.30°~45° C.25°~30° D.10°~40°
A.2mB.3mC.4mD.5m
A.40~65N/m B.20~30N/m C.30~40N/m D.70~80N/m
A.拉伸 B.扭转 C.弯曲疲劳 D.变形