The objective of this work is to demonstrate the feasibility of friction stir welding (FSW) AISI 304 austenitic stainless steels. The tool used was formed of a tungsten-based alloy. The specimens were welded on an 11 kW vertical milling machine. Defect-free welds were produced on 2.5 mm plates of hot-rolled AISI 304 austenitic stainless steels at travel speeds ranging from 40 to 100 mm/ min with a constant rotating speed of 1000 rpm. Tensile strengths and hardness values of the weld interface were determined and microstructure features of these samples were investigated.Keywords

In recent years, one of the main challenges is to improve the mechanical performance of bio-composites to be used as structural parts for the construction, automotive, and aviation sector. This paper may contribute to developing durable structural bio-composite parts with starch addition. The mechanical properties of bio-composites reinforced by eucalyptus or pine fibers (48 wt %) compound with Cationic Starch (48 wt %) and Carboxymethyl cellulose (CMC) (4 wt %) were determined. The production method was a combination of molded pulp, extrusion, and compression molding production techniques. To see the effect of adding starch to bio-composites and different production methods, the mechanical performance of these natural fibers produced by the conventional molded pulp production method (without any additives) was also found and compared with the composite samples. Composite samples indicate significantly better tensile, flexural, and compressive values, at least four times, compared with the molded pulp samples. On the other hand, the molded pulp samples had more than 2 times better impact characteristics against composites. Using molded pulp technic in composite production (investigated in the study) is a new idea and may give some opportunities with its serial production compatibility and geometry freeness, to the industry.