Fabrication of SiC particle reinforced composite on aluminium surface by friction stir processing

Abstract

A feasibility investigation has been carried out of the formation of surface composite by uniformly distributing SiC particles 1?25 mm in size into a surface layer of an A 1050-H24 Al plate through friction stir processing (FSP). The SiC particle was filled into a groove cut on the Al plate, covered by an Al sheet 2 mm thick, and a rotating tool was penetrated from the cover sheet so that the probe tip reached a depth beyond the groove bottom. The effects of process parameters (rotation speed and travelling speed) and applying multiple passes on the distribution of SiC particle in the nugget zone were investigated. The effects of groove size and its position relative to the tool probe were also investigated. Applying multiple passes had a great effect on the homogeneity of the SiC particle distribution. At rotation speeds of 2000-3000 rev min 21 , the SiC particles tended to cluster in some places in the nugget zone. By decreasing the rotation speed to 1000-1500 rev min 21 , the SiC particle was distributed in almost all the nugget zone area when the groove was 2-3 mm wide and 1?5 mm deep. On the other hand, the stirring action of FSP was insufficient to distribute homogenously the SiC particles when the groove size was increased to 362 mm. By shifting the groove position towards the advancing side of the tool probe, the distribution of the SiC particles in the nugget zone became better. The defect free nugget zone with homogenously distributed SiC particles was obtained in a sample produced by FSP at rotation speeds of 1500 rev min 21 for the first pass and 1250 rev min 21 for the second and third passes. Microhardness of the nugget zone was increased to a level as high as 55 HV when the groove size was 361?5 mm. The effect of the rotation speed on the particles dispersion was discussed with particular reference to the vertical material flow in the nugget zone.

Fabrication of Surface-Hybrid-MMCs Layer on Aluminum Plate by Friction Stir Processing and Its Wear Characteristics

“…These conditions produced the best results in terms of homogeneity of the particles inside the nugget zone for producing the SMMCs of the pure Al reinforced with SiC particles. 39,40) Double and triple passes were applied in order to improve the homogeneity of the reinforcement particle distribution. In the second pass, the tool was travelled along the same line as the first and third ones but in the opposite direction.…”

“…29,32,33) It is considered that SMMCs are one of the latest applications of FSP. [34][35][36][37][38][39][40] The stirring action and frictional heat generated by the FSP tool can be used to distribute ceramic particles as reinforcement on the surface of light metals like aluminum and magnesium. [34][35][36][37][38][39][40] The present authors 39,40) succeeded in uniformly distributing SiC particles of 1.25 mm size in a surface layer of a few mm thickness on Al 1050-H24 plates to form surface composites by FSP.…”

Characterization of Aluminum Alloy-Based Nanocomposites Produced by the Addition of Al-Ti5-B1 to the Matrix Melt

“…Besides its low density and low cost, SiC enhances an increase in the Young's modulus, hardness and tensile strength. However, these composites suffer from a great loss in ductility and toughness due to the undesirable reactions between SiC particles and aluminum, yielding Al 4 C 3 interfacial product, which limits their applications to a certain extent (Mahmoud et al, 2008). On the other hand, Titanium diboride (TiB 2 ) has distinct advantages over SiC because of its inertness to aluminum matrix (Shackelford and Alexander, 2001).…”

Friction-stir processing of a composite aluminium alloy (AA 1050) reinforced with titanium carbide powder

“…2 Mahmoud et al fabricated AA1050/SiC SMMC, their results showed that the distribution of the SiC particles became more homogeneous with an increasing number of passes and with the combination of tool rotational speed and the processing speed resulted in the formation of defects, such as voids and tunnels in the FSP zone. 20 E. R. I. Mahmoud et al 20 also fabricated AA1050/SiC SMMC and assessed the effect of the tool pin size and profile. From their results, the wear rates of the samples produced with the flat surface tools were higher than that of the samples produced with the round-shaped tools and the samples produced with the square profile pin yielded a finer distribution of the SiC particles.…”

“…The welding process was carried out by rotating 1500 min -1 and by moving 200 mm/min. Under a constant friction force this involved four different shoulder diameters of (20,25,30 and 40) mm. During welding, temperature measurements were performed using a non-contact laser thermometer at various parts of the plates from the welding centre outwards.…”