two different dual phase steels were prepared from low carbon manganese steel after the eliminationof the banding using the direct quenching (dq) and the step quenching (sq) procedures. different heattreatments resulted in different martensite morphologies, microstructures and mechanical properties. theheat treatments were designed in such a way to obtain a 0.25 volume fraction of martensite (v...

Impact testing methodology is findings the applications for determining the impact strength of the different materials. Oneof the most important characteristics of structural steels, toughness is assessed by the Charpy V-notch impact test. The objective of the research was to maximize the impact toughness by selecting various combinations of Charpy Impact test parameters. In this paper, experim...

High strength steels Q690+Q550 were welded using three different welding wires without preheating by gas shielded arc welding process. Microstructural characteristics of weld metals and nucleation mechanism of acicular ferrite were investigated by means of scanning electron microscope (SEM), energy dispersive spectrum (EDS) and transmission electron microscope (TEM). The straight Y-groove test ...

A procedure i s presented f o r determining the impact f r a c t u r e toughness K w i t h precracked Charpy specimens wi thout performing any load measurements.'?he Kid-val ue i s obtained from preestabl ished impact response curves and a measurement o f t h e t ime-to-fracture. The measuring technique i s f u l l y dynamic and does not impose any r e s t r i c t i o n s on t h e t e s t condi...

The suitability of high-strength ultrafine and nanocrystalline materials processed by severe plastic deformation methods and aimed to be used for structural applications will strongly depend on their resistance against crack growth. In this contribution some general available findings on the damage tolerance of this material class will be summarized. Particularly, the occurrence of a pronounced...

The relationship between alloying content, microstructure and properties has been studied for high strength steel weld metals with 7 to 9 wt. % nickel. Neural network modelling suggested that manganese reductions lead to large impact toughness increases and that nickel must be added in a controlled manner with respect to manganese in order toincrease impact toughness. Carbon additions were pred...

Toughening of polyamide 6 (PA6)/ Nanoclay (NC) nanocomposites with styrene-ethylene/butadiene-styrene copolymer (SEBS) using maleated styrene-ethylene/butadiene-styrene copolymer (mSEBS)/ as a compatibilizer were investigated by blending them in a co-rotating twin-screw extruder. Response surface method of experimental design was used for optimizing the material and processing parameters. Effec...

Primate species often eat foods of different physical properties. This may have implications for tooth structure and wear in those species. The purpose of this study was to examine the mechanical defenses of leaves eaten by Alouatta palliata from different social groups at Hacienda La Pacifica in Costa Rica. Leaves were sampled from the home-ranges of groups living in different microhabitats. S...

The increasing need in the mechanical testing of sub-sized samples motivated the present study focused on the effect of the size of samples. Sometimes, attempts are made, due to economic reasons, to replace testing of the fracture toughness by a cheaper testing of notch toughness. Several empirical relations, pertaining to relations between fracture toughness and energy consumption in impact te...