scholarly journals Suitability of technical materials for machinery subsoilers for soil tillage

Author(s):  
Radek Bednář ◽  
Jiří Votava ◽  
Jan Červinka ◽  
Martin Fajman

Agricultural soil processing belongs to the basic elements in the process of crop production. Currently classic tillage method is decreasing and the only trend has stated as a shallow plowing. Suitable post harvest soil tillage greatly affects yields in the next cycle. The aim of the study is the analysis of abrasive wear of selected construction materials and their subsequent use for DXRV-HD cultivator. The performed tests are focused on monitoring the mechanical properties of the materials and their use for variable cutting tip of cultivator body. Tested materials are divided into four categories. These materials include tool steel (19436), carbon steel (12050), cast iron with globular graphite and welding material supplied as a functional complex on low carbon steel by the Abraweld company. These materials are tested together with the original part of share cultivator. The present experiment is focused on metallorgraphic, mechanical and abrasive analysis. Structural component of the material is identified by metallographic photos and then compared with the impact strength tested on Charpy hammer. Followed the abrasion resistance according to CSN 01 5084 and the total evaluation of the tested samples are done.

2021 ◽  
Vol 1016 ◽  
pp. 42-49
Author(s):  
Kook Soo Bang ◽  
Joo Hyeon Cha ◽  
Kyu Tae Han ◽  
Hong Chul Jeong

The present work investigated the effects of Al, Si, and N content on the impact toughness of the coarse-grained heat-affected zone (CGHAZ) of Ti-containing low-carbon steel. Simulated CGHAZ of differing Al, Si, and N contents were prepared, and Charpy impact toughness was determined. The results were interpreted in terms of microstructure, especially martensite-austenite (M-A) constituent. All elements accelerated ferrite transformation in CGHAZ but at the same time increased the amount of M-A constituent, thereby deteriorating CGHAZ toughness. It is believed that Al, Si, and free N that is uncombined with Ti retard the decomposition of austenite into pearlite and increase the carbon content in the last transforming austenite, thus increasing the amount of M-A constituent. Regardless of the amount of ferrite in CGHAZ, its toughness decreased linearly with an increase of M-A constituent in this experiment, indicating that HAZ toughness is predominantly affected by the presence of M-A constituent. When a comparison of the effectiveness is made between Al and Si, it showed that a decrease in Si content is more effective in reducing M-A constituents.


2009 ◽  
Vol 79-82 ◽  
pp. 143-146
Author(s):  
Jiang Hua Ma ◽  
Dong Ping Zhan ◽  
Zhou Hua Jiang ◽  
Ji Cheng He

In order to understand the effects of deoxidizer such as aluminium, titanium and magnesium on the impact toughness of heat affected zone (HAZ), three low carbon steels deoxidized by Ti-Al, Mg and Ti-Mg were obtained. After smelting, forging, rolling and welding simulation, the effects of Al, Ti and Mg addition on the impact toughness of HAZ in low carbon steel were studied. The inclusion characteristics (size, morphology and chemistry) of samples before welding and the fracture pattern of the specimens after the Charpy-type test were respectively analyzed using optical microscope and scanning electron microscopy (SEM). The following results were found. The density of inclusion in Ti-Mg deoxidized steel is bigger than Ti-Al deoxidized steel. The average diameter is decreased for the former than the latter. The addition of Ti-Mg can enhance the impact toughness of the HAZ after welding simulation. The maximal value of the impact toughness is 66.5J/cm2. The complex particles of MgO-TiOx-SiO2-MnS are most benefit to enhance impact toughness. The improvement of HAZ is attributable to the role of particle pinning and the formation of intergranular ferrite.


Metals ◽  
2018 ◽  
Vol 8 (10) ◽  
pp. 747 ◽  
Author(s):  
Farnoosh Forouzan ◽  
M. Guitar ◽  
Esa Vuorinen ◽  
Frank Mücklich

To improve the weld zone properties of Advanced High Strength Steel (AHSS), quenching and partitioning (Q&P) has been used immediately after laser welding of a low-carbon steel. However, the mechanical properties can be affected for several reasons: (i) The carbon content and amount of retained austenite, bainite, and fresh martensite; (ii) Precipitate size and distribution; (iii) Grain size. In this work, carbon movements during the partitioning stage and prediction of Ti (C, N), and MoC precipitation at different partitioning temperatures have been simulated by using Thermocalc, Dictra, and TC-PRISMA. Verification and comparison of the experimental results were performed by optical microscopy, X-ray diffraction (XRD), Scanning Electron Microscop (SEM), and Scanning Transmission Electron Microscopy (STEM), and Energy Dispersive Spectroscopy (EDS) and Electron Backscatter Scanning Diffraction (EBSD) analysis were used to investigate the effect of martensitic/bainitic packet size. Results show that the increase in the number density of small precipitates in the sample partitioned at 640 °C compensates for the increase in crystallographic packets size. The strength and ductility values are kept at a high level, but the impact toughness will decrease considerably.


2017 ◽  
Vol 62 (2) ◽  
pp. 483-487 ◽  
Author(s):  
M. Suliga ◽  
R. Wartacz ◽  
J. Michalczyk

Abstract The paper contains the theoretical and experimental analysis of the impact of the drawing angle on the drawing process and the properties of low carbon steel wires. A multi-stage drawing wire rod with a diameter of 5.5 mm on a wire with a diameter of 1.0 mm has been carried out in two stages. The first one consisted of preliminary drawing wire rod for the wire with a diameter of 2.2 mm which was next subjected to the drawing process at a speed of 25 m/sec at the final wire with a diameter of 1.0 mm. The wires were drawn in conventional dies with drawing angle α = 3, 4, 5, 6, 7 degrees. For the wires drawn in respective variants, the investigation of the mechanical properties was performed and the amount of lubricant on the surface of steel wires was determined. Numerical analysis of the process of drawing in the Drawing 2D complemented the experimental studies. It has been shown that when drawing at high speeds, properly chosen the value of the angle of the working part of the die can improve the lubrication conditions and mechanical properties of steel wires.


2021 ◽  
Vol 12 (2) ◽  
pp. 30-37
Author(s):  
Rico Arifandi ◽  
Gerald Adityo Pohan

In the military field, tank is armored fighting vehicles that move using chain-shaped wheels. The tread of the tank chain is a component to tread and move so that it requires tougher properties on the surface and has ductile and tough properties on the inside and is more resistant to wear on the surface. The development of tank chain production materials is necessary for the independence of national defense and security as well as reducing dependence on imports. Imported tank chain hardness value 28 HRC or 286 HV. In this research, the objective of this research is to increase the surface hardness of the steel by carburizing the initial material, especially the low carbon steel ST-37. The carburizing treatment process is a method of adding carbon content in steel using solid media. The carbon media used were mangrove charcoal and tamarind wood charcoal using calcium carbonate (CaCO3) catalyst at a constant heating temperature of 900ºC, variations in holding time of 30 minutes, 60 minutes and 90 minutes, cooled rapidly with water media. Then performed an analysis of the effect of the type of wood charcoal on the mechanical properties of carbon steel ST-37. The results obtained will be applied to the tank chain tread production process. The results of the micro structure of martensite and the highest hardness value were found in the holding time of 60 minutes of mangrove charcoal media with the microstructure results of 63.8% martensite, 36.2% bainite and a hardness value of 453.1 HV. The highest toughness value is found in the holding time of 60 minutes of tamarind wood charcoal media with an impact price (HI) of 0.4345 J/mm2. The difference between the impact test results of tamarind charcoal media with mangroves is not too significant. The higher the martensite phase, the higher the hardness value. However, there is also a bainite phase which can increase the toughness of the steel which will be used as a tread chain production material.


2018 ◽  
Vol 786 ◽  
pp. 57-64 ◽  
Author(s):  
Ahmed Hamed ◽  
Mamdouh Eissa ◽  
Abdelhakim Kandil ◽  
Omnia Ali ◽  
Taha M. Mattar

This work aims at designing and developing low carbon steel alloys to meet the high tensile strength, high ductility and high impact toughness properties. The effect of solid solution mechanism, precipitation hardening, as well as grain refinement were developed with different Manganese content (0.78-2.36wt%) combined with Vanadium(0.008-0.1wt%) and Titanium (0.002-0.072wt%) microalloying additions. The controlled thermo-mechanical treatments and chemical compositions play a big role in developing the microstructure and the corresponding mechanical properties. Therefore, the studied chemical compositions were treated thermo-mechanically by two different ways of changing start and finish forging temperatures with subsequent air cooling. The first way by start forging from 1050 to 830oC and the second from 950 to730oC. The second way of forging process developed finer grain sizes and higher ultimate tensile strengths for all the studied steel alloys. In spite of finer grain sizes, the impact toughness value was lower in the second regime due to detrimental influence of precipitation strengthening in the ferrite. A combination of 544 MPa yield strength, 615 MPa ultimate tensile strength, 20% elongation and 138 Joule impact toughness has been attained.


2016 ◽  
Vol 61 (1) ◽  
pp. 15-18 ◽  
Author(s):  
I. M. Safarov ◽  
A. V. Korznikov ◽  
R. M. Galeyev ◽  
S. N. Sergeev ◽  
S. V. Gladkovsky ◽  
...  

Author(s):  
Jenan Mohammed Naje ◽  
Nidaa Hameed Dawood ◽  
Sara Saad Ghazi

This paper explores the effect of ultrasonic peening using various passes on an impact strength of AISI 1020 low carbon steel. Many ASTM E23 impact specimens were prepared from the chosen metal and exposed to multi-pass ultrasonic peening (1,2,3 pass). Microstructure, hardness, residual stresses, and impact tests on ultrasonic peened and not peened samples were performed. Ultrasonic peening contributed to increasing the impact strength, due to the increase in comparative residual stress and hardness. Three passes show improvement in strength by (29.7%), comparative with the base metal.


Author(s):  
Brian D. Hawkes ◽  
Kenneth R. Durstine

A shielded cask is used to transport radioactive materials between facilities. The cask was fabricated with an outer and inner shell of hot rolled low carbon steel. Lead was poured in the annular space between the shells to provide radiation shielding. Carbon steel is known to be susceptible to low-temperature brittle fracture under impact loading. This paper will present the analysis results representing postulated transportation accidents during on-site transfers of the cask. The accident scenarios were based on a series of cask drops onto a rigid surface from a height of 6 ft assuming brittle failure of the cask shell at subzero temperatures. Finite element models of the cask and its contents were solved and post processed using ABAQUS software. Each model was examined for failure to contain radioactive materials and/or significant loss of radiation shielding. Results of these analyses show that the body of the cask exhibits considerable ruggedness and will remain largely intact after the impact. There will be deformation of the main cask body with localized brittle failure of the cask outer shell and components and but no complete penetration of the cask shielding. The cask payload outer waste can will experience some permanent plastic deformation in each drop, but will not be deformed to the point where it will rupture, thus maintaining confinement of the can contents.


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