帮助理解下,多谢!? maximum permissible hardness is rockwell c35 immediately under thread roots and shall be taken on a flat area at least 3,5 mm across, prepared by removing threads; no more material than necessary shall be removed to prepare the flat area. 在丝牙根部最大允许硬度是罗氏c35,应在至少3.5mm平面上通过去除丝牙取样,不得超出需要平面区域所需的材料。查看更多