The transverse properties of two commercial hydroforming tubes with different D/t ratios were obtained using the newly developed RHTT. We found that: Transverse properties of these tubes are different from the sheet properties and tube longitudinal properties. Work hardening during tube marking can change the material behavior significantly, especially for small D/t ratio tubes. Tube flattening can cause additional changes in the transverse properties of tubes. The most interesting find was a marked loss of elongation after tube making in the higher strength steel used to make the smaller tube. Also significant was the change in properties associated with flattening for the flattened transverse strip tensile test. Transverse tube properties, especially yield strength and elongation, vary around the tube circumference. Higher yield strengths were observed at the 180-degree position and near the edges of the strip. Tensile properties are changed when the sheet is subjected to roll forming, and they depend on test specimen orientation. Properties are further changed if specimens are subjected to flattening.
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