Comparison of different sensor technologies to monitor a forging process

Nowadays, numerical simulations are more and more used in forging industry, and their predictability is validated through a comparison with experiments. But sometimes simulations and experiments provide significantly different results. And quite often, the models implemented in simulations are taken for responsible of this divergence with experimental results. But results experimentally obtained can also be discussed. Depending on the operatory conditions, and the type of sensor used, measured results can be different. Moreover, integrating sensors is not an easy task for forging processes, as sensors could be exposed to harsh environment with high speeds, high forces, high temperatures, radiations, … In this paper data for displacement and force measured by different sensors are compared. Advantages of different sensor technology are discussed in the case of hot forging processes performed with energy piloted machines.

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Flash Design for Automatic Transfer System of Bearing Hub in Hot Forging Process

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.116-117.120 ◽

2006 ◽

Vol 116-117 ◽

pp. 120-123

Author(s):

Sang Kon Lee ◽

Hyun Sang Byun ◽

Byung Min Kim ◽

Dae Cheol Ko ◽

C.G. Kang

Keyword(s):

Numerical Analysis ◽

Metal Flow ◽

Hot Forging ◽

Experimental Results ◽

Transfer System ◽

Forging Process ◽

Hot Forging Die ◽

Forging Die ◽

Hot Forging Process ◽

Forging Load

The aim of this study is to design flash geometry of bearing hub to apply the automatic transfer system in hot forging process. The flash geometry is very important in hot forging process because the flash geometry effects on the metal flow, material losses, forging load, die pressure and so on. In this study, the problem of designing the flash geometry is studied with flash thickness and width considering the maximum die pressure to apply an automatic transfer system in hot forging process for bearing hub. The numerical analysis was conducted by means of the commercial S/W DEFORM. On the basis of numerical analysis the flash geometry of hot forging die was redesigned, and experiment was conducted. From the experimental results, it was possible to produce bearing hub with an automatic transfer system without any deterioration of die lifetime.

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Case Study of the Effect of Precoating on the Decarburization of the Surface Layer of Forged Parts during the Hot Die Forging Process

10.20944/preprints202012.0246.v1 ◽

2020 ◽

Author(s):

Paweł Widomski ◽

Maciej Zwierzchowski ◽

Artur Barełkowski ◽

Mateusz Tympalski

Keyword(s):

Surface Layer ◽

High Temperatures ◽

Induction Heating ◽

Laboratory Tests ◽

Hot Forging ◽

Forging Process ◽

Induction Heater ◽

Forged Parts ◽

Hot Die Forging

Based on tests results, the possibility of using this solution in the technique of industrial hot forging was evaluated. The results of laboratory tests have confirmed that lubrication of metal pieces is sufficient as well as proved it to be effective in reducing decarburization of the surface layer. Research works conducted in an induction heater showed differences in decarburization depending on a substance and concentration of lubricants that were used. These differences become more apparent when observing the surface layer of the forged parts. Results indicate that decarburization may be reduced to a minimum when we use Bonderite product in a concentration of 66% and 50%. Another lubricant, Berulit 913, may also be used. However, due to burning graphite in high temperatures, reduction of decarburization goes only as far as half of the thickness of the decarbonized layer. Condursal has no significant effect; nevertheless, it protects over the induction heating stage.

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Finite Element Simulation of Hot Forging Process for KVBM Gear

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.875.30 ◽

2018 ◽

Vol 875 ◽

pp. 30-35 ◽

Cited By ~ 1

Author(s):

Sethapong Wangchaichune ◽

Surasak Suranuntchai

Keyword(s):

Finite Element ◽

Plastic Strain ◽

Effective Stress ◽

Hot Forging ◽

Experimental Results ◽

Effective Plastic Strain ◽

Fe Method ◽

Modeling And Analysis ◽

Forging Process ◽

Initial Billet

In this study, the forging operations of gear has been modeled. This gear is a part which is manufactured with the help of hot forging industry for reduce the cost. The authors propose to reduce the initial billet volume of AISI 4340 steel for the forged through process optimization using the Finite Element (FE)method. The object of this research was to predict the effect of several parameters, such as effective stress, effective plastic strain, temperature and die contact, on the forming of the gear, utilizing computer simulation and experimental results. For this purpose, Solidworks CAD and Simufact Forming FE software were used for the modeling and analysis of the forging process. The billet volume and the preform design were predefined in order to reduce scrap by using preform type C. The experimental results showed that the initial billet volume was reduced at 32 %, which compared favorably with the simulation result of a 40 % reduction. The maximum preforming force of simulation result was diferent with the experiment result at 18 along with the maximum finishing force of simulation result was different with the experiment result at 11 %. It was also found that the effective stress decreased with increasing the temperature, and the press force decreased when the initial billet volume was decreased, which resulted in a decrease of effective plastic strain as well.

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Hot Deformation Behavior and Dynamic Recrystallization of Ultra High Strength Steel

Metals ◽

10.3390/met11081239 ◽

2021 ◽

Vol 11 (8) ◽

pp. 1239

Author(s):

Liping Zhong ◽

Bo Wang ◽

Chundong Hu ◽

Jieyu Zhang ◽

Yu Yao

Keyword(s):

Martensitic Steel ◽

High Strength ◽

Experimental Results ◽

Hot Deformation Behavior ◽

Thermal Compression ◽

Forging Process ◽

Finite Element Software ◽

Ultra High Strength Steel ◽

Recrystallized Grain Size ◽

Deform 3D

In this paper, in order to improve the microstructure uniformity of an ultra-high strength martensitic steel with a strength greater than 2500 MPa developed by multi-directional forging in the laboratory, a single-pass hot compression experiment with the strain rate of 0.01 to 1 s−1 and a temperature of 800 to 1150 °C was conducted. Based on the experimental data, the material parameters were determined, the constitutive model considering the influence of work hardening, the recrystallization softening on the dislocation density, and the recrystallized grain size model were established. After introducing the model into the finite element software DEFORM-3D, the thermal compression experiment was simulated, and the results were consistent with the experimental results. The rule for obtaining forging stock with a uniform and refinement microstructure was acquired by comparing the simulation and the experimental results, which are helpful to formulate an appropriate forging process.

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Advanced Complex Analysis of the Thermal Softening of Nitrided Layers in Tools during Hot Die Forging

Materials ◽

10.3390/ma14020355 ◽

2021 ◽

Vol 14 (2) ◽

pp. 355

Author(s):

Jakub Krawczyk ◽

Paweł Widomski ◽

Marcin Kaszuba

Keyword(s):

Numerical Modeling ◽

Surface Layer ◽

Laboratory Tests ◽

Complex Analysis ◽

Nitrided Layer ◽

Hot Forging ◽

Thermal Softening ◽

Effect Of Temperature ◽

Destructive Effect ◽

Forging Process

This article is devoted to the issues of thermal softening of materials in the surface layer of forging tools. The research covers numerical modeling of the forging process, laboratory tests of tempering of nitrided layers, and the analysis of tempering of the surface layer of tools in the actual forging process. Numerical modeling was supported by measuring the temperature inside the tools with a thermocouple inserted into the tool to measure the temperature as close to the surface as possible. The modeling results confirmed the possibility of tempering the die material. The results of laboratory tests made it possible to determine the influence of temperature on tempering at different surface layer depths. Numerical analysis and measurement of surface layer microhardness of tools revealed the destructive effect of temperature during forging on the tempering of the nitrided layer and on the material layers located deeper below the nitrided layer. The results have shown that in the hot forging processes carried out in accordance with the adopted technology, the surface layer of working tools is overheated locally to a temperature above 600 °C and tempering occurs. Moreover, overheating effects are visible, because the surface layer is tempered to a depth of 0.3 mm. Finally, such tempering processes lead to a decrease in the die hardness, which causes accelerated wear because of the abrasion and plastic deformation. The nitriding does not protect against the tempering phenomenon, but only delays the material softening process, because tempering occurs in the nitrided layer and in the layers deeper under the nitrided layer. Below the nitrided layer, tempering occurs relatively quickly and a soft layer is formed with a hardness below 400 HV.

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