scholarly journals Application of a Novel Chamfered Mold to Suppress Corner Transverse Cracking of Micro-Alloyed Steel Slabs

Metals ◽  
2020 ◽  
Vol 10 (10) ◽  
pp. 1289
Author(s):  
Guoliang Liu ◽  
Qing Liu ◽  
Chenxi Ji ◽  
Bin Chen ◽  
Haibo Li ◽  
...  
Keyword(s):  
Design Method ◽  
Steel Production ◽  
Alloyed Steel ◽  
Interstitial Free ◽  
Solidification Shrinkage ◽  
Transverse Cracking ◽  
Steel Grades ◽  
Steel Slabs ◽  
Micro Alloyed Steel

A novel chamfered mold is developed to solve the problem of corner transverse cracking in micro-alloyed steel slabs. The shape of the slab was changed from four corners and sides to eight corners and sides due to the use of a chamfered mold. Based on numerical simulation, the solidification and heat transfer of different steel grades in the mold are studied. The results reveal rapid solidification shrinkage of molten steel in the upper area of the mold and slow solidification shrinkage in the lower area; thus, a double-taper mold is designed according to these results. The first area of the variable taper falls in the range of 250–400 mm from the top of the mold, and the design method of double inclined water channels in the chamfered face is found to be the most helpful for the formation of a uniform initial shell and reducing hotspots of the mold. Actual production results show that the quality of the slab is better when the heat flux of the narrow face is larger than that of the broad face. Corner transverse cracking in micro-alloyed steels is greatly reduced from an incidence of 4.2% to less than 0.3%. In addition, the chamfered mold is applied in IF (interstitial free) steel production, and the edge quality of hot rolled sheets is found to also be dramatically improved.

Modification of MnS inclusion by tellurium in 38MnVS6 micro-alloyed steel

2020 ◽  
Vol 117 (6) ◽  
pp. 615
Author(s):  
Ping Shen ◽  
Lei Zhou ◽  
Qiankun Yang ◽  
Zhiqi Zeng ◽  
Kenan Ai ◽  
...  
Keyword(s):  
Fatigue Life ◽  
Aspect Ratio ◽  
Strong Influence ◽  
Experimental Results ◽  
Alloyed Steel ◽  
Equivalent Diameter ◽  
Small Aspect Ratio ◽  
Steel Quality ◽  
Eds Analysis ◽  
Micro Alloyed Steel

In 38MnVS6 steel, the morphology of sulfide inclusion has a strong influence on the fatigue life and machinability of the steel. In most cases, the MnS inclusions show strip morphology after rolling, which significantly affects the steel quality. Usually, the MnS inclusion with a spherical morphology is the best morphology for the steel quality. In the present work, tellurium was applied to 38MnVS6 micro-alloyed steel to control the MnS inclusion. Trace tellurium was added into 38MnVS6 steel and the effect of Te on the morphology, composition, size and distribution of MnS inclusions were investigated. Experimental results show that with the increase of Te content, the equivalent diameter and the aspect ratio of inclusion decrease strikingly, and the number of inclusions with small aspect ratio increases. The inclusions are dissociated and spherized. The SEM-EDS analysis indicates that the trace Te mainly dissolves in MnS inclusion. Once the MnS is saturated with Te, MnTe starts to generate and wraps MnS. The critical Te/S value for the formation of MnTe in the 38MnV6 steel is determined to be approximately 0.075. With the increase of Te/S ratio, the aspect ratio of MnS inclusion decreases and gradually reaches a constant level. The Te/S value in the 38MnVS6 steel corresponding to the change of aspect ratio from decreasing to constant ranges from 0.096 to 0.255. This is most likely to be caused by the saturation of Te in the MnS inclusion. After adding Te in the steel, rod-like MnS inclusion is modified to small inclusion and the smaller the MnS inclusion, the lower the aspect ratio.

COMPARATIVE PERFORMANCE EVALUATION OF PMB and CRMB WITH PARTIAL REPLACEMENT OF BITUMEN (VG-30) USING MARSHALL MIX DESIGN METHOD-A REVIEW

2018 ◽  
Vol 5 (02) ◽  
Author(s):  
N. SATHEESHKANNA
Keyword(s):  
Performance Evaluation ◽  
Design Method ◽  
Mix Design ◽  
Partial Replacement ◽  
Comparative Performance

Waste generated from industries and from various places around us not only contains rubber or plastics but contains lot many harmful pollutants whichare hazardous if disposed continuously in open and leftto degrade in our environment.Our project aims to study properties of different materials which may help in utilising the waste as well as improve the quality of roads and make them efficient, stable, durable and long lasting. Some of the materials that we have studied and considered to be tested in the partial replacement of bitumen are PMB and CRMB.

Research on the Optimal Design Method of the Main Components for the Wheelchair Pickup

2013 ◽  
Vol 791-793 ◽  
pp. 799-802
Author(s):  
Ya Ping Wang ◽  
H.R. Shi ◽  
L. Gao ◽  
Z. Wang ◽  
X.Y. Jia ◽  
...  
Keyword(s):  
Parametric Design ◽  
Design Method ◽  
Basic Function ◽  
Design Parameters ◽  
Algorithm Optimization ◽  
Optimization Analysis ◽  
Research Designs ◽  
Optimal Design Method ◽  
Main Components

With the increasing of the aging of population all over the world, and With the inconvenience coming from diseases and damage, there will be more and more people using the wheelchair as a tool for transport. When it cant be short of the wheelchair in the daily life, the addition of the function will bring the elevation of the quality of life for the unfortunate. Staring with this purpose, the research designs a pickup with planetary bevel gear for the wheelchair. After determining the basic function of the wheelchair aids, the study determines the design parameters by using the knowledge of parametric design and completes the model for the system with Pro/E, on the other hand, it completes key components optimization analysis which is based on genetic algorithm optimization.

Horizontal CCMs in small-capacity metallurgy

2021 ◽  
Vol 77 (7) ◽  
pp. 776-781
Author(s):  
V. V. Reshetov ◽  
A. I. Trushin
Keyword(s):  
Small Volume ◽  
Alloyed Steel ◽  
Rolled Stock ◽  
Light Section ◽  
Wide Range ◽  
Central Porosity ◽  
Steel Grades ◽  
Horizontal Type ◽  
First Time ◽  
Small Capacity

Production of light-section rolled products and wire rods of alloyed steel grades differs by small volume of yearly output and wide range of smelted grades. To organize production of light-section rolled products of alloyed steel grades in small volumes, OJSC “Spetsmash” elaborated concept of small-capacity production, which was implemented at several plants. It was shown that horizontal CCM can be effectively applied in the small-capacity production within complexes of light-section rolled stock of alloyed steels production. At the plant “Ferrotrade” (Beloretsk) when creating a complex for production wire rods of 6.5 mm diameter of austenite class steels and nickel-based alloys, a horizontal CCM was constructed. Production of 60 mm diameter billets by the machine was mastered, which enabled to apply a rolling mini-mill, characterizing by small dimensions and power. The horizontal CCM, constructed in 2016 at the steelmaking shop of CJSC “Izhevsk pilot-mechanical plant”, was equipped by electromagnetic stirrer (EMS). It was noted that EMS was applied for the first time in domestic metallurgy at the industrial CCM of horizontal type. In the process of this CCM mastering, more than 60 heats were casted into billets of 80, 200 and 120 mm diameter. EMS application resulted in improving average point on the central porosity to 1.2—1.8 depending on the stirring modes. In 2018 the OJSC “Spetsmash” for the Research Center “Thermodeform” (Magnitogorsk) constructed an experimental horizontal CCM, designed for casting of billets of 40—60 mm diameter by direct casting of melt from the crucible of 60 kg induction furnace into the metal reservoir 776 of the machine. Development of a project of horizontal CCM for PJSC “PlasmaTek” (Ukraine, Vinnitsy) finished, designed for production of billets of 50 and 60 mm diameter within a complex of equipment for manufacturing welding electrodes not only of alloyed but also of carbon steel grades. The designed productivity of the complex is 12,000 t/year. Basic technical characteristics of the CCM presented. Small-capacity production with horizontal CCMs can be organized as independent objects and within existing steel-works for expanding product range.

Automatic verification method of progressive image model matching information based on machine learning

2021 ◽  
pp. 1-10
Author(s):  
Jie Yuan ◽  
Yuan Ji ◽  
Zhou Zhu ◽  
Liya Huang ◽  
Junfeng Qian ◽  
...  
Keyword(s):  
Machine Learning ◽  
Learning Algorithm ◽  
Design Method ◽  
Large Error ◽  
Model Matching ◽  
Target Image ◽  
Image Model ◽  
Verification Method ◽  
Low Performance

In order to solve the problems of large error and low performance of traditional progressive image model matching information checking methods, an automatic progressive image model matching information checking method based on machine learning is proposed. The generation method of progressive image is analyzed, and the target image sample is obtained. On this basis, machine learning algorithm is used to segment progressive image samples. In each image segmentation part, crawler technology is used to automatically collect progressive image model matching information, and under the constraint of image model matching information checking standard, automatic checking of progressive image model matching information is realized from geometric structure, image content and other aspects. Experimental results show that the verification error of the design method is reduced by 0.687 Mb, and the quality of progressive image is improved.

Spectrum imaging and three-dimensional atom probe studies of fine particles in a vanadium micro-alloyed steel

2008 ◽  
Vol 24 (6) ◽  
pp. 641-650 ◽  
Author(s):  
A. J. Craven ◽  
M. MacKenzie ◽  
A. Cerezo ◽  
T. Godfrey ◽  
P. H. Clifton
Keyword(s):  
Fine Particles ◽  
Three Dimensional ◽  
Atom Probe ◽  
Alloyed Steel ◽  
Spectrum Imaging ◽  
Micro Alloyed Steel
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