Evaluation and Repair of Wrought Iron and - Purdue e-Pubs ...

88stresses are induced. These permanent deformations clearly removed some of theductility available in the material, thus making it less ductile. This parallels thehypothesis that the rectangular testing coupons have less ductility than the round testingcoupons as a result of damage that effectively reduced the amount of plastic strain thatwas available in the material. Therefore, significantly straightening a damaged specimenwithout heat reduces the plastic strain ductility of the specimen, and thus reduces thepercent elongation exhibited by the material.4.4.6 Results of Welded SpecimensFive tensile coupon specimens were cut in half and then welded before testing.The procedure that was used in welding these specimens was discussed in Chapter 3.Before testing, a macrograph was taken of the welded material to determine if the weldfully penetrated the wrought iron material. Figure 4.17 shows this macrograph andindicates that there was full penetration of the weld material. The macrograph alsoindicates that only a slight inclusion was created.During testing none of the welded specimens failed within the region of the weld.Therefore, the weld demonstrated to be was stronger than the wrought iron material andcould be considered a satisfactory weld detail. When comparing the tensile strength ofthe welded specimens to the other tensile coupons from the Bell Ford bridge that had notbeen welded, there is little variation between them, as shown in Figure 4.18. There wasalso little variation of the yield strength between the welded and non-welded specimens.When investigating the percent elongation of the welded and non-weldedspecimens, the welded specimens consistently had a lower percent elongation, as shownin Figure 4.19. Even though the percent elongation values of the welded samples werefound to be lower, the reduction in ductility was not large enough to question the validityof the weld detail.