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The purpose of this paper is to join aluminium alloy AA6061 with polyvinyl chloride (PVC) sheets using the friction spot technique.

The AA6061 specimen was drilled with a semi-conical hole and put over the PVC specimen with a lap configuration. A friction spot technique was used to generate the required heat to melt and extrude the PVC through the aluminium hole. In this study, three process parameters were used: time, plunging depth and rotating speed of the tool. Thermal finite element model was built to analyse the process temperature. Effect of the process parameters on the joint shear strength and temperature was analysed using the design of experiments method. The microstructure investigation of the joint cross section was examined.

The input heat melted and extruded the polymer into the aluminium hole with the aid of tool pressure. A mechanical interlock was observed at the interface line between the polymer and aluminium. The scattered aluminium fragments into the molten polymer increased the shear strength of the joint. The hole diameter exhibited the highest effect on the joint strength compared with the other parameters. Specimen of minimum hole diameter recorded the maximum shear strength of 224 MPa. The proposed model gave a good agreement with the experimental data.

For the first time, the PVC was joined with AA6061 by the hot extrusion using the friction spot technique. The shear strength of joint reached 7.5 times of the base material (PVC).

The purpose of this paper is to join sheets of an aluminium alloy together with pre-holed carbon steel via friction spot technique.

An AISI 1006 steel sheet was a pre-holed with a 4.8 mm diameter and put under AA5052 sheet with a lap joint configuration. The joining process was carried out by extruding the aluminium through the steel hole using a rotating tool of 10 mm diameter. Furthermore, three process parameters (pre-heating time, rotating speed and plunging depth of the tool) with three values for each parameter were used to study their effects on the joints quality. In order to join samples, nine experiments were designed according to a Taguchi method. Shear strength, microstructure and X-ray diffraction tests of the joint were carried out.

The joining mechanism occurred by a mechanical interlock of the extruded aluminium with the inner surface of the steel hole. The tool plunging depth had a significant effect on the shear strength of the joint. The shear strength of two joints exceeded the shear strength of the wrought material (AA5052). All samples failed with two modes: pull-out and shearing of the extruded aluminium.

For the first time, the extrusion technique was used to join AA5052 sheet together with pre-holed carbon steel, with a perfect joint efficiency.

The purpose of this paper is to join AA5052 to AISI 1006 steel sheets using the spot friction forming technique.

A steel sheet was pre-holed with a diameter of 4.8 mm and pre-threaded with a single internal M6 thread. Lap joint configuration was used so that the aluminium specimen was put over steel. A rotating tool with a 10 mm diameter was used for the joining process. A Taguchi method was used to design three process parameters (plunging tool depth, rotating speed and preheating time), with three levels for each parameter. The effect of the process parameters on the joint shear strength was analysed. The macrostructure, microstructure and scanning electron microscope of the joint were investigated. The temperature distribution during the joining process was recorded.

The formed aluminium was extruded through the steel hole and penetrated through the thread slot. A mechanical interlock was achieved between the extruded aluminium and the steel. The plunging depth of the tool exhibited a significant effect on the joint shear strength. The joint efficiency increased gradually as the plunging depth increased. Two modes of failure were found shear and pull-out. The maximum temperature during the process reached 50 per cent of aluminium’s melting point.

For the first time, AA5052 was joined with AISI 1006 steel using a friction spot forming technique with an excellent joint efficiency.

The purpose of this paper is to join a sheet of the AA7075 with the high-density polyethylene (HDPE) by a lap joint using friction spot processing and investigate the temperature distribution of joint during this process using the finite element method (FEM).

A semi-conical hole was manufactured in the AA7075 specimen and a lap joint configuration was prepared with the HDPE specimen. A rotating tool was used to generate the required heat to melt the polymer by the friction with the AA7075 specimen. The applied tool force moved the molten polymer through the hole. Four parameters were used: lower diameter of hole, rotating speed, plunging depth and time. The results of shear test were analyzed using the Taguchi method. A FEM was presented to estimate the temperature distribution of joint during the process.

All specimens failed by shearing the polymer at the lap joint region without dislocation. The specimens of the smallest diameter exhibited the highest shear strength at the lap joint. The maximum ranges of temperature were recorded at the contact region between the rotating tool and the AA7075 specimen. The tool plunging depth recorded the highest effect on the generated heat compared with the rotating speed and plunging time.

For the first time, the AA7075 sheet was joined with the HDPE sheet by friction spot processing. The temperature distribution of this joint was simulated using the FEM.

The purpose of this paper is to optimize the welding parameters: rotating speed and plunging depth of carbon steel and pure copper joints using friction stir spot welding (FSSW) with the aid of the design of experiments (DOE) method.

Carbon steel and pure copper sheets were welded using the FSSW technique with a cylindrical tool and without a probe. The welding parameters were: rotating speed: 1,120, 1,400 and 1,800 RPM and plunging depth: 0.2 and 0.4 mm. The welding process was carried out both with and without pre-heating. The welded specimens were analyzed using a shear tensile test. A microstructural investigation at the optimum conditions was carried out. The results were analyzed and optimized using the statistical software Minitab and following the DOE method.

Pre-heating the sample and increasing the rotating speed and plunging depth increased the tensile shear force of the joint. The plunging depth has the biggest effect on the joint efficiency compared with the rotating speed. The optimum shear force (4,560 N) was found at 1,800 RPM, 0.4 mm plunge depth and with pre-heating. The welding parameters were modified so that the samples were welded at 1,800 RPM and at plunging depths of 0.45–1 mm in 0.05 mm steps. The optimized shear force was 5,400 N. The fractured samples exhibited two types of failure mode: interfacial and nugget pull-out.

For the first time, pure copper and carbon steel sheets were welded using FSSW and a tool without a probe with ideal joint efficiency (95 percent).