Welding of High Carbon Steel without Transformation
A high carbon steel joint, S70C (0.72wt%C) was successfully friction stir welded without any postheat treatments. There are two methods for obtaining proper joint properties. The first method is to decrease the peak temperature to below A1, and the other method to decrease the cooling rate to less than the lower critical cooling rate. As a result, the ultimate tensile strength of 1214 MPa, 0.2 % proof strength of 700 MPa and elongation of 40% were obtained for a joint.
S.W. Nam, Y.W. Chang, S.B. Lee and N.J. Kim
H. Fujii et al., "Welding of High Carbon Steel without Transformation", Key Engineering Materials, Vols. 345-346, pp. 1411-1415, 2007