Friction stir welding (FSW) is an emerging manufacturing technology for aerospace structures. It will see widespread use in the future as it offers ways of creating lighter structures at lower manufacturing cost than traditional methods (riveting, adhesive bonding). Since its invention in 1991, FSW has known fast improvements and many studies have demonstrated its capability for joining a wide ...

The laser-ultrasonic technique is proposed for defect detection and residual stress measurement in friction stir welds (FSW). When combined with the synthetic aperture focusing technique (F-SAFT), very good performances are achieved for detecting lack of penetration in butt joints, the detection limit coinciding with the conditions of reduced mechanical properties. Also, the detection of kissin...

The study presents the hybrid joining of third generation AA2198-T8 aluminum lithium alloy to AA2024-T3 copper alloy, which has been highly demanded recently in aerospace industry. This investigation aims reduce cost production industrial sector. As a result, an affordable alternative is use designs using crucial parts and rest structure. A method required create structures composed last-genera...

Objectives. This study examined correlates of condom use among 248 female sex workers (FSW) in The Gambia. Methods. Between July and August 2011, FSW in The Gambia who were older than 16 years of age, the age of consent in The Gambia, were recruited for the study using venue-based sampling and snowball sampling, beginning with seeds who were established clients with the Network of AIDS Services...

This article presents a method for automatic seam-tracking in friction stir welding (FSW) of lap joints. In this method, tracking is accomplished by weaving the FSW tool back-and-forth perpendicular to the direction of travel during welding and monitoring force and torque signals. Research demonstrates the ability of this method to automatically track weld seam positions. Additionally, tensile ...

A three-dimensional heat transfer model for friction stir welding (FSW) is presented in this paper; a moving coordinate is introduced to reduce the difficulty of modeling the moving tool. Heat input from the tool shoulder and the tool pin are considered in the model. The finite difference method was applied in solving the control equations. A non-uniform grid mesh is generated for the calculati...

A spacecraft simulation environment was developed for testing distributed spacecraft flight software (FSW) designed for autonomous coordinated control of a spacecraft cluster. The Cluster Flight Application (CFA) FSW was developed by Emergent Space Technologies in support of the Defense Advanced Research Projects Agency (DARPA) System F6 Program. The CFA provides cluster flight guidance, naviga...

One of the interesting state-of-the-art approaches to welding is the process of friction stir welding (FSW). In comparison with the fusion processes, FSW is an advantageous method as it is suitable for the non-fusion weldable alloys and polymeric materials joining. Regarding the materials pure solid state joining, it also provides joints with less distortion and enhanced mechanical properties. ...

BACKGROUND In a study of female sex workers (FSW) servicing truck driver clients in Mexican border cities, we evaluated differences in HIV/STI risk behaviors by workplace. METHODS Cross-sectional study of FSW servicing truck drivers in Mexico: 100 from Nuevo Laredo (U.S. border); 100 from Ciudad Hidalgo (Guatemalan border). Main outcome was unstable workplace, defined as primary place of sex ...

This paper introduces a perpetual type-2 Neuro-Fuzzy modelling structure for continuous learning and its application to the complex thermo-mechanical metal process of steel Friction Stir Welding (FSW). The ‘perpetual’ property refers to the capability of the proposed system to continuously learn from new process data, in an incremental learning fashion. This is particularly important in industr...