• 2022-07-26
    钢板厚度为t,剪切屈服极限ts,剪切强度极限tb。若用冲床在钢板上冲出直径为d 的圆孔,则冲头的冲压力应不小于( )。[img=192x172]1803e330554032f.png[/img]
    A: [img=51x32]1803e3305d699c8.png[/img]
    B: [img=48x35]1803e330663a88b.png[/img]
    C: [img=73x53]1803e3306f14242.png[/img]
    D: [img=79x58]1803e33076f3b32.png[/img]
  • 举一反三