1,ASTM 4340 Alloy Steel Flat Bar 2,Thickness:10~90mm 3,Width:60~610mm ... : Name: ASTM 4340 Alloy Steel Flat Bar Place of Origin:Liaoning,China Brand Name:Dongbei Tegang Shape:Flat Bar Material:Alloy Steel Steel Grade: AISI 4340 ... components of high strength such as aircraft engine ,cross beam,undercarrige,pressure vessel,rocket hull,heavy-load torsion shaft,etc.Chemical composition ...