scholarly journals Neural Network Based Adaptation Algorithm for Online Prediction of Mechanical Properties of Steel

2020 ◽  
Vol 2 (2) ◽  
Author(s):  
S. Rath

After production of a steel product in a steel plant, a sample of the product is tested in a laboratory for its mechanical properties like yield strength (YS), ultimate tensile strength (UTS) and percentage elongation. This paper describes a mathematical model based method which can predict the mechanical properties without testing. A neural network based adaptation algorithm was developed to reduce the prediction error. The uniqueness of this adaptation algorithm is that the model trains itself very fast when predicted and measured data are incorporated to the model. Based on the algorithm, an ASP.Net based intranet website has also been developed for calculation of the mechanical properties. In the starting Furnace Module webpage,  austenite grain size is calculated using semi-empirical equations of austenite grain size during heating of slab in a reheating furnace. In the Mill Module webpage, different conditions of static, dynamic and metadynamic recrystallization are calculated. In this module, austenite grain size is calculated from the recrystallization conditions using corresponding recrystallization and grain growth equations. The last module is a cooling module. In this module, the phase transformation equations are used to predict the grain size of ferrite phase. In this module, structure-property correlation is used to predict the final mechanical properties. In the  Training Module,  the neural network based adapation algorithm trains the model and stores the weights and bias in a database for future predictions. Finally, the model was trained and validated with measured property data. 

Materials ◽  
2021 ◽  
Vol 14 (8) ◽  
pp. 1988
Author(s):  
Tibor Kvackaj ◽  
Jana Bidulská ◽  
Róbert Bidulský

This review paper concerns the development of the chemical compositions and controlled processes of rolling and cooling steels to increase their mechanical properties and reduce weight and production costs. The paper analyzes the basic differences among high-strength steel (HSS), advanced high-strength steel (AHSS) and ultra-high-strength steel (UHSS) depending on differences in their final microstructural components, chemical composition, alloying elements and strengthening contributions to determine strength and mechanical properties. HSS is characterized by a final single-phase structure with reduced perlite content, while AHSS has a final structure of two-phase to multiphase. UHSS is characterized by a single-phase or multiphase structure. The yield strength of the steels have the following value intervals: HSS, 180–550 MPa; AHSS, 260–900 MPa; UHSS, 600–960 MPa. In addition to strength properties, the ductility of these steel grades is also an important parameter. AHSS steel has the best ductility, followed by HSS and UHSS. Within the HSS steel group, high-strength low-alloy (HSLA) steel represents a special subgroup characterized by the use of microalloying elements for special strength and plastic properties. An important parameter determining the strength properties of these steels is the grain-size diameter of the final structure, which depends on the processing conditions of the previous austenitic structure. The influence of reheating temperatures (TReh) and the holding time at the reheating temperature (tReh) of C–Mn–Nb–V HSLA steel was investigated in detail. Mathematical equations describing changes in the diameter of austenite grain size (dγ), depending on reheating temperature and holding time, were derived by the authors. The coordinates of the point where normal grain growth turned abnormal was determined. These coordinates for testing steel are the reheating conditions TReh = 1060 °C, tReh = 1800 s at the diameter of austenite grain size dγ = 100 μm.


2002 ◽  
Vol 43 (5) ◽  
pp. 916-919 ◽  
Author(s):  
Jorge Otubo ◽  
Fabiana C. Nascimento ◽  
Paulo R. Mei ◽  
Lisandro P. Cardoso ◽  
Michael J. Kaufman

Metals ◽  
2019 ◽  
Vol 9 (5) ◽  
pp. 577 ◽  
Author(s):  
Sebastian Härtel ◽  
Birgit Awiszus ◽  
Marcel Graf ◽  
Alexander Nitsche ◽  
Marcus Böhme ◽  
...  

This paper examines how the initial austenite grain size in quench and partitioning (Q-P) processes influences the final mechanical properties of Q-P steels. Differences in austenite grain size distribution may result, for example, from uneven heating rates of semi-finished products prior to a forging process. In order to quantify this influence, a carefully defined heat treatment of a cylindrical specimen made of the Q-P-capable 42SiCr steel was performed in a dilatometer. Different austenite grain sizes were adjusted by a pre-treatment before the actual Q-P process. The resulting mechanical properties were determined using the upsetting test and the corresponding microstructures were analyzed by scanning electron microscopy (SEM). These investigations show that a larger austenite grain size prior to Q-P processing leads to a slightly lower strength as well as to a coarser martensitic microstructure in the Q-P-treated material.


2016 ◽  
Vol 666 ◽  
pp. 207-213 ◽  
Author(s):  
Tao Jiang ◽  
Hongji Liu ◽  
Junjie Sun ◽  
Shengwu Guo ◽  
Yongning Liu

Sign in / Sign up

Export Citation Format

Share Document