Free forming of locally laser heated parts

Özmen, Murat
As metals have high formability at elevated temperatures, hot forming is preferred and widely used in manufacturing of complicated geometries. The term أhot formingؤ is usually used if the whole workpiece is processed at elevated temperatures. However, for certain products high formability is required only locally. Forming by local heating is proposed to provide ease of manufacturing of local forms on the workpiece. Also, tools can be simplified by this method. In this study, local laser heating procedures are applied to obtain local forms on cylindrical bulk metal products in a single step. Locally heated workpieces are formed between two flat dies. Both solid and hollow products have been investigated experimentally and by finite element modeling. The experimental studies and finite element analyses are done simultaneously in order to obtain optimum local deformation characteristics. Three different materials together with different initial geometries and various local laser-heating procedures are applied to search for the process window. The limits of applicability are determined and examples of application are supplied.


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Hot forming is highly utilized in manufacturing of complex shapes. Relatively low flow stresses of materials at elevated temperatures provide ease of manufacturing. On the other side, the current trend is to replace hot forming with cold forming due to the superior mechanical properties and higher dimensional accuracy of the products and less energy consumption. However, cold forming requires high tooling costs and forming loads. In this study, a new process is proposed for production of complex shaped prod...
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Moisture absorption in polymers and polymeric composites is well known to lead to significant degradation in mechanical properties. Most epoxy based composites may absorb 2 to 5 wt.% moisture when they are subjected to humid environments. Moisture absorption in polymers has been often characterized with Fickian or various non-Fickian models to describe the time-dependent absorption phenomena. Previous experiments have shown that dispersing moderate amounts of nanoclay in an epoxy resin can: (i) reduce the t...
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Thermoelectric (TE) polymers have unique advantages in converting heat into electricity. But their Seebeck coefficient is lower than that of inorganic TE materials by about one order of magnitude. Here, surface energy filtering is proposed to significantly enhance the Seebeck coefficient of TE polymers. The as-prepared poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS, the most popular TE polymer) films from aqueous solution have a low Seebeck coefficient of 15-18 mu V K(-1)and a power fact...
Citation Formats
M. Özmen, “Free forming of locally laser heated parts,” M.S. - Master of Science, Middle East Technical University, 2005.