METAL PIPE AND STRUCTURAL MEMBER USING METAL PIPE FOR VEHICLE

A metal pipe has a quadrangular cross section. The metal pipe includes a pair of side walls and facing each other and having a height H, a top portion connected to an upper edge of each of the pair of side walls and and a bottom portion connected to a lower edge of each of the pair of side walls and The metal pipe has a length six times the height H of the side walls and or more. Each of the pair of side walls and includes a high-strength portion A or A and a pair of low-strength portions B or B. Each high-strength portion A or A has a dimension not less than (⅔) H and not more than 3 H as measured in the longitudinal direction of the metal pipe, the high-strength portions forming opposite portions of the pair of side walls and each high-strength portion having a yield strength not less than 500 MPa. The low-strength portions B or B sandwich the high-strength portion A or A as determined along the longitudinal direction of the metal pipe, each low-strength portion having a yield strength of CO to 85% of that of the high-strength portion A or A.