Fatigue strength characteristics of S35C/S35C friction welded tubular butt joints.

Abstract

By using S35C/S35C friction welded tubular butt joints fabricated under five different friction welding processes, a series of tests were conducted to determine the effect of welding conditions on joint performance. At first, the hardness measurement revealed that, though the extent of heat affected zone was different from each other depending on the welding condition, no noticeable difference was observed in the maximum hardness value at the weld interface of joint. Then, the results of monotonic tensile tests indicated that the joint efficiencies of four joints were sufficiently high excepting only one joint fabricated under the lowest friction pressure condition. But the above-mentioned results did not necessarily reflect on the fatigue strength of the joints, and their fatigue strength behaviors could be subdivided into two groups as follows: Two types of joints showed lower fatigue strength than that of the base material and appeared to have no fatigue limit in the range of this experiment; and in contrast, the fatigue strength of the other three types of joints well exceeded that of the base material and showed a tendency to have a fatigue limit. Such fatigue strength behaviors seemed to be correlated closely to the magnitude of forging pressure in the friction welding process.

Friction welding technique and joint properties of thin-walled pipe friction-welded joint between type 6063 aluminum alloy and AISI 304 austenitic stainless steel

“…For example, Kawai et al [14] and Ohkubo et al [15] showed the results for the joint between various aluminum (Al) alloy and mild carbon steel, which had a wall thickness (referred to as pipe thickness) of 3 mm. However, research on the friction welding of circular pipe of dissimilar combination has been scant in comparison with that of similar combination such as those reports described by Eberhard et al [16], Ogawa et al [17], and Kumar and Balasubramanian [18]. Furthermore, those investigations were carried out using relatively thick pipe thickness that was thicker than 1 mm, i.e., the ratio of the pipe thickness to the outside diameter of the pipe was larger than 0.1.…”

Determination of the Mechanical Properties of Friction Welded Tube Yoke and Tube Joint

“…Researchers, who studied the friction welding of tubular sections with a ratio ( / ) larger than 0.1, reported that the joining of tubular sections having similar materials could be successfully achieved [14,15]. The friction welding method for thin walled tubular sections with a ratio ( / ) of 0.1 and less was studied by Kimura et al [16] and Kumar and Balasubramanian [17].…”