Experimental and thermomechanical analysis of the effect of tool pin profile on the friction stir welding of poly(methyl methacrylate) sheets. (August 2018)

• Record Type: Journal Article
• Authors: Aghajani Derazkola, Hamed; Simchi, Abdolreza
• Is Part Of: Journal of manufacturing processes. Volume 34:Part A(2018)
• Page Start: 412
• Page End: 423
• Publication Date: 2018-08
• Subjects: Friction stir welding -- PMMA -- Tool pin profile -- Mechanical property -- Material flow -- Thermomechanical model; Production management -- Data processing -- Periodicals; Manufacturing processes -- Periodicals; Procestechnologie; Productietechniek; Production -- Gestion -- Informatique -- Périodiques; Fabrication -- Périodiques; Manufacturing processes; Production management -- Data processing; Periodicals; 670.5
• DOI: 10.1016/j.jmapro.2018.06.015
• Languages: English
• ISSNs: 1526-6125

Abstract

Abstract: Effects of frustum, cubic and triangle tool pin profiles on the friction stir welding (FSW) of poly(methyl methacrylate) (PMMA) were studied by experimental analysis and thermomechanical simulations. It is shown that employing pins with a low contact surface area form macrocracks and voids along the joint line. Edged-type pins locally stir the polymer and cause tunnel defects which are formed at the root of the joint. In contrast, pins with relatively smooth and large surface area would yield a defect-free weldment if an appropriate processing condition is employed. Mechanical examinations in longitudinal (LS) and transverse (TS) directions indicate that the highest tensile strength (LS = 59 MPa and TS = 43 MPa) of the joint is attained for the frustum pin. The result of Izod test also determines a higher impact energy of the joint for the frustum pin as well. Fractographic studies indicate that cracks are initiated from internal defects and voids, propagating through the material to cause brittle rupture. Interestingly, the effect of pin geometry on the tensile strength and impact energy is different than that hardness (in ShoreD scale).