الفهرس 
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Abstract
In the present study, FSSW was adopted to weld AA2024 aluminum alloy
sheets with both polycarbonate (PC) and polypropylene (PP) sheets using two different tools having two different pin configurations. The two tools have conical pin with 2.5 mm height, however, tool (T1) has draft angle of 16.69o and the tool
(T2) has a draft angle of 6o
.The effects of FSSW process parameters, typically, the tool rotational speeds and dwell time, on peak temperature variation in the
tool/workpiece interface was also recorded, via an infrared (IR) camera. Moreover, the influence of the aforementioned FSSW process parameters on the microstructural and the mechanical characteristics of AA2024-Al/PC and AA2024- Al/PP lap joints were investigated. The results revealed that increasing the dwell time and/or the tool rotational
speed increase(s) the peak temperature in FSSW of both AA2024-
Al/polycarbonate and AA2024-Al/polypropylene welded joints. For AA2024- Al/polycarbonate joints, the peak temperatures recorded for tool T1 are higher than those recorded using tool T2. The peak temperature ranges were found to vary from 54 to 150 oC and from 45 to 136 oC, for joints welded using T1 and T2 tools,
respectively. While, for AA2024-Al/polypropylene joints, the peak temperatures recorded for tool T2 are higher than those recorded using tool T1. The peak temperature ranges were found to vary from 40 to 115 oC and from 61 to 143 oC, for joints welded using T1 and T2 tools, respectively.
For AA2024/polycarbonate joints welded using T1 tool, increasing the tool
rotational speed and/or the dwell time increase(s) the tensile-shear force. The AA2024/polycarbonate tensile-shear samples joined using T2 tool and the tool rotational speeds up to 1000 rpm showed an increase in the mean tensile-shear force with increasing the dwell time up to 6 seconds. At higher tool rotational speed (i.e. 1500 rpm), the increase in the dwell time from 4 to 6 sec. reduces the tensile shear force. While, for AA2024/polypropylene joints welded using T2 tool, at constant tool rotational speed, increasing the dwell time increases the tensile- 3
shear force. In contrast, at constant dwell time, increasing the tool rotational speed slightly reduces or sometimes has no effect on the tensile-shear force. The analysis of variance (ANOVA) results showed that the dwell have the highest statistical and physical influence on the peak temperature followed by the
tool rotational speed, tool type and polymer material. While, the type of the polymer material (PM) exhibited the highest statistical and physical influence on the tensile-shear force followed by the tool rotational speed, dwell time and, finally, the tool type.