The fatigue fracture reason of the weld seam at the back supporting rod of the main reductor of an aircraft has been analyzed by fractography and metallographic test. 对某飞机主减速器后撑杆焊缝疲劳断裂原因作了分析。
The back is another board held on by eight screws. 背板用八个螺钉固定。
Heavyweight, black nylon with reinforced back panel padding. 质感黑色尼龙为材料，填充背板，方便舒适。
