The maximum strength observed for dissimilar PA 6-PA 66 butt-welds was 66 MPa.
The TF-weld strengths were consistently lower than those of the butt-welds. In general, lower T-weld strength has been attributed to stress concentrations at the corner in the web-flange joint (9-11).
Results for butt-welds made at low weld pressure (0.66 MPa) and high weld pressure (4.7 MPa) at a constant penetration of 1 mm are shown in Fig.
Figure 14 shows the effect of increasing pressure from 0.66 MPa to 4.7 MPa at a meltdown of 1 mm for butt-welds. It shows that the thickness of the heataffected zone in the weld region increases as the weld pressure is decreased.
Experimental Data Used to Develop Polynomial Model as Well as Additional Experimental Runs for Butt-Welds. Each Data Point Represents the Average of 5 Coupons Machined From One Welded Assembly.