A Study on Forging Characteristic of Non-Heat Treated Micro-Alloyed Steel Using Finite Element Analysis

The aim of the present investigation was to calculate the stress distribution generated in the root dentine canal during mechanical rotation of five different NiTi endodontic instruments by means of a finite element analysis (FEA). Two conventional alloy NiTi instruments F360 25/04 and F6 Skytaper 25/06, in comparison to three heat treated alloys NiTI Hyflex CM 25/04, Protaper Next 25/06 and One Curve 25/06 were considered and analyzed. The instruments’ flexibility (reaction force) and geometrical features (cross section, conicity) were previously investigated. For each instrument, dentine root canals with two different elastic moduli(18 and 42 GPa) were simulated with defined apical ratios. Ten different CAD instrument models were created and their mechanical behaviors were analyzed by a 3D-FEA. Static structural analyses were performed with a non-failure condition, since a linear elastic behavior was assumed for all components. All the instruments generated a stress area concentration in correspondence to the root canal curvature at approx. 7 mm from the apex. The maximum values were found when instruments were analyzed in the highest elastic modulus dentine canal. Strain and von Mises stress patterns showed a higher concentration in the first part of curved radius of all the instruments. Conventional Ni-Ti endodontic instruments demonstrated higher stress magnitudes, regardless of the conicity of 4% and 6%, and they showed the highest von Mises stress values in sound, as well as in mineralized dentine canals. Heat-treated endodontic instruments with higher flexibility values showed a reduced stress concentration map. Hyflex CM 25/04 displayed the lowest von Mises stress values of, respectively, 35.73 and 44.30 GPa for sound and mineralized dentine. The mechanical behavior of all rotary endodontic instruments was influenced by the different elastic moduli and by the dentine canal rigidity.

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Microstructure evolution and fracture behavior of heat treated enamel coating: Experiment and finite element analysis

Surface and Coatings Technology ◽

10.1016/j.surfcoat.2021.127826 ◽

2021 ◽

Vol 427 ◽

pp. 127826

Author(s):

Gaosheng Yan ◽

Wenshan Yu ◽

Shengping Shen

Keyword(s):

Finite Element Analysis ◽

Finite Element ◽

Microstructure Evolution ◽

Fracture Behavior ◽

Enamel Coating ◽

Element Analysis ◽

Heat Treated

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Finite Element Analysis for Deep Drawing of Tailored Heat Treated Blanks

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.6-8.343 ◽

2005 ◽

Vol 6-8 ◽

pp. 343-352 ◽

Cited By ~ 2

Author(s):

M. Kerausch ◽

Marion Merklein ◽

Detlev Staud

Keyword(s):

Mechanical Properties ◽

Finite Element Analysis ◽

Finite Element ◽

Aluminum Alloys ◽

Deep Drawing ◽

General Idea ◽

Drawing Process ◽

Element Analysis ◽

Car Body ◽

Heat Treated

Aluminum alloys, due to their low density compared to steels, are an important group of materials, in particular for light weight construction of transport vehicles. However, aside from their low specific weight, drawing of car body components made from aluminum alloys is limited by an inferior formability. To enable a modern car body design, it is necessary to enhance the formability of aluminum sheet metal. One basic approach to reach this aim is to adapt the mechanical properties of the blank for the drawing process. The general idea is to soften the deformation zone relative to the force transferring zone, which results in an improved material flow and thus to larger drawing depths. In this paper the process sequence consisting of local induction heat treatment followed by deep drawing of precipitation hardenable aluminum alloy is presented. Using an induction system, it is possible to change the mechanical properties of the 6xxx aluminum blanks in a restricted area by influencing the precipitation structure. Tensile tests characterize the conversion from the stable naturally aged condition T4 to reversible solution heat treated W conditions of AA6016 as function of temperature and time. This effect leads to a reduction of flow stress, which is used to design an material property distribution adapted for the subsequent deep drawing process. A process characterization study provides detailed information concerning induction heating parameters, to improve the deep drawing of cylindrical cups, which results in a decisive increase of the limiting drawing ratio. Accompanying the experimental investigations, a finite element analysis approach is realized as a process design and optimization tool. Following the presented strategy, it is possible to enhance the forming capability of aluminum alloys. This leads to advanced manufacturing processes, which extend the field of applications for aluminum car body parts.

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