PSI - Issue 5

George Pantazopoulos et al. / Procedia Structural Integrity 5 (2017) 476–483 G. Pantazopoulos and A. Vazdirvanidis/ Structural Integrity Procedia 00 (2017) 000 – 000

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d. In both cases ( Hexagonal brass fittings and Threaded brass components ), Pb accumulation and “pool - formation” was observed on the intergranular fracture facets, suggesting that Pb wetting reduced the grain / interface boundary energy facilitating decohesion and fracture. e. The above findings indicated that metal-induced embrittlement was the plausible failure mechanism, activated as a result of excess-heating during fabrication process (hot shortness). Sufficient adjustment of temperature, by controlled heating (or cooling) in combination to the selection of optimum fabrication speed is recommended in order to minimize the risk of future failures. Dieter, G.E., (1988). Mechanical Metallurgy. McGraw Hill, 1988. Garcia P., Rivera, S., Palacios, M., Belzunce, J., (2010). Comparative study of the parameters influencing the machinability of leaded brasses, Engineering Failure Analysis, 17(4), 771 – 776 Laporte, V., Mortensen, A., (2009). Intermediate temperature embrittlement of copper alloys. International Materials Reviews 54(2), 94-116. Lynch, S.P., (2008). Failure of structures and components by metal-induced embrittlement. J Failure Analysis and Prevention 8(3), 218-222. Pantazopoulos, G., (2002). Leaded brass rods C 38500 for automatic machining operations: a technical report. J Materials Engineering and Performance 11, 402-407. Pantazopoulos, G., (2003). A review of defects and failures in brass rods and related components. Journal of Failure Analysis and Prevention 3 (4), 14-22. Pantazopoulos, G., Vazdirvanidis, A., (2008). Characterization of the microstructura l aspects of machinable α - β phase brass. Microscopy and Analysis 22, 13-16. Pantazopoulos, G., Vazdirvanidis, A., (2008). Failure analysis of a fractured leaded-Brass (CuZn39Pb3) extruded hexagonal rod. J Failure Analysis and Prevention 8, 218-222. Pantazopoulos, G.A., Toulfatzis, A.I., (2012). Fracture modes and mechanical characteristics of machinable brass rods. Metallography, Microstructure, and Analysis, 1(2), 106-114. Pantazopoulos, G.A., Toulfatzis, A.I., (2013). Failure analysis of a machinable brass connector in a boiler unit Installation, Case Studies in Engineering Failure Analysis, 1, 18-23. Toulfatzis, A.I., Besseris, G.J., Pantazopoulos, G.A., Stergiou, C., (2011). Characterization and comparative machinability investigation of extruded and drawn copper alloys using non-parametric multiresponse optimization and orthogonal arrays, International Journal of Advanced Manufacturing Technology, 57(5 – 8), 811 – 826. Wolley, D.J., Fox, A., (1988). The embrittlement of leaded and unleaded α + β (60-40) brasses in the temperature range 300 to 500°C. J. Materials Science Letters 7, 763-765. References