scholarly journals Application of ductile iron in the manufacture of ploughshares

2012 ◽  
Vol 50 (No. 2) ◽  
pp. 75-80 ◽  
Author(s):  
R. Březina ◽  
J. Filípek ◽  
J. Šenberger

The service life and reliability of machines for basic soil cultivation is mainly affected by abrasive wear. The working tools of these machines are mostly made of steel. The paper deals with the possibility of manufacturing ploughshares and reversible points of austempered ductile iron (ADI). The authors examine the abrasion resistance of ADI working tools and compare it with that of the material applied by a leading world manufacturer of ploughshares. Using an appropriate mode of the heat treatment of ADI, abrasion resistance comparable to that of the original tools can be obtained.

2018 ◽  
Vol 27 (11) ◽  
pp. 5865-5878 ◽  
Author(s):  
Dorota Wilk-Kołodziejczyk ◽  
Krzysztof Regulski ◽  
Tomasz Giętka ◽  
Grzegorz Gumienny ◽  
Krzysztof Jaśkowiec ◽  
...  

2018 ◽  
Vol 12 (4) ◽  
pp. 4180-4190
Author(s):  
Ananda Hegde ◽  
Sathyashankara Sharma ◽  
Gowri Shankar M. C

When the ductile iron which is also known as Spheroidal Graphite (SG) iron, is subjected to austempering heat treatment, the material is known as austempered ductile iron (ADI). This material has good mechanical properties and has various applications in different fields. This revolutionary material with its excellent combination of strength, ductility, toughness and wear resistance has the potential to replace some of the commonly used conventional materials such as steel, aluminium and other light weight alloys as it offers production advantage as well. One of the problems encountered during manufacturing is machining of ADI parts owing to its high hardness and wear resistance. Many researchers over a period of time have reported the machinability aspects of the ADI. This paper presents a review on the developments made on the machinability aspects of ADI along with other mechanical properties.


2014 ◽  
Vol 14 (4) ◽  
pp. 49-54 ◽  
Author(s):  
A. Krzyńska ◽  
A. Kochański

Abstract Austenitization is the first step of heat treatment preceding the isothermal quenching of ductile iron in austempered ductile iron (ADI) manufacturing. Usually, the starting material for the ADI production is ductile iron with more convenient pearlitic matrix. In this paper we present the results of research concerning the austenitizing of ductile iron with ferritic matrix, where all carbon dissolved in austenite must come from graphite nodules. The scope of research includedcarrying out the process of austenitization at 900° Cusing a variable times ranging from 5 to 240minutes,and then observations of the microstructure of the samples after different austenitizing times. These were supplemented with micro-hardness testing. The research showed that the process of saturating austenite with carbon is limited by the rate of dissolution of carbon from nodular graphite precipitates


2021 ◽  
Vol 14 ◽  
Author(s):  
Lakshmiprasad Maddi ◽  
Ajay Likhite

Background: Ductile irons provide a more viable alternative for malleable cast iron in areas that do not demand extreme wear resistance. Austempering of ductile irons was a well researched area in the last two decades. Attempts to further improve the wear resistance led to the development of Carbidic austempered ductile iron (CADI), wherein the carbides contribute to wear resistance. Combination of ausferritic matrix, graphite nodules, and carbides (eutectic and alloy) symbolizes the microstructure of CADI. Methods: Two principal approaches adopted by the researchers to change the microstructure are (i) addition of carbide forming elements (ii) heat treatment (s). Results: Both the above methods result in the refinement of graphite nodules, carbide precipitations, along with fine ausferrite. Conclusion: Improvement in hardness, toughness and wear resistance was observed largely as a consequence of fine carbide precipitations and formation of martensite.


Materials ◽  
2020 ◽  
Vol 13 (22) ◽  
pp. 5266
Author(s):  
Martin Landesberger ◽  
Robert Koos ◽  
Michael Hofmann ◽  
Xiaohu Li ◽  
Torben Boll ◽  
...  

The phase transformation to ausferrite during austempered ductile iron (ADI) heat treatment can be significantly influenced by the alloying element Mo. Utilizing neutron diffraction, the phase transformation from austenite to ausferrite was monitored in-situ during the heat treatment. In addition to the phase volume fractions, the carbon enrichment of retained austenite was investigated. The results from neutron diffraction were compared to the macroscopic length change from dilatometer measurements. They show that the dilatometer data are only of limited use for the investigation of ausferrite formation. However, they allow deriving the time of maximum carbon accumulation in the retained austenite. In addition, the transformation of austenite during ausferritization was investigated using metallographic methods. Finally, the distribution of the alloying elements in the vicinity of the austenite/ferrite interface zone was shown by atom probe tomography (APT) measurements. C and Mn were enriched within the interface, while Si concentration was reduced. The Mo concentration in ferrite, interface and austentite stayed at the same level. The delay of austenite decay during Stage II reaction caused by Mo was studied in detail at 400 °C for the initial material as well as for 0.25 mass % and 0.50 mass % Mo additions.


Author(s):  
T. R. Uma ◽  
J. B. Simha ◽  
K. Narasimha Murthy

Laboratory abrasive wear tests have been reported on permanent moulded toughened austempered ductile iron. The influence of austempering temperature on the abrasive wear behavior have been studied and discussed. The results indicate that with increase in austempering temperature from 300°C to 350°C, the abrasive wear resistance increased, and as the austempering temperature increased to 400°C, there was reduction in the abrasive wear resistance. These results have been interpreted based on the structural features and graphite morphology.


2020 ◽  
Vol 835 ◽  
pp. 163-170
Author(s):  
Hayam A. Aly ◽  
Adel Nofal ◽  
Abdel Hamid A. Hussein ◽  
Elsayed M. El-Banna

This study aimed at optimizing impact toughness and high wear resistant carbidic austempered ductile iron (CADI) by controlling the morphology, size and quantity of carbides. The effects of dynamic solidification, niobium addition, combined action of them and heat treatment have been investigated. Investigations were performed by means of the image analyzer, scanning electron microscopy (SEM), energy-dispersive spectrometry (EDS) and X-ray diffraction. Impact toughness, hardness and abrasion wear resistance tests were conducted. Fracture surfaces were studied. Results indicated that microstructural control during solidification is the most valuable tool to attain the optimum combination between impact toughness and wear resistance in CADI. Combined action of Nb addition and dynamic solidification improves impact toughness, hardness and wear resistance even more than the action of each individual factor. In the as-cast condition, impact toughness, hardness and abrasion resistance were improved after dynamic solidification compared to statically solidify one by 31.2%, 18.75% and 87.96% respectively. This enhancement was increased to 36.9%, 25.93% and 128. % by adding 1% Nb. Lower tempering temperature of 275°C exhibit best hardness and abrasion resistance better than higher tempering temperature of 375°C.


Author(s):  
A Fernández-Valdivielso ◽  
LN López de Lacalle ◽  
P Fernández-Lucio ◽  
H González

Austempered ductile iron castings (ADI) are characterized by the high strength and resistance to fatigue, impact, and wear. ADI mechanical properties are obtained by performing a heat treatment on ductile iron casting. Thus, the so-called ausferrite microstructure is achieved. However, heat treatment significantly affects ductile casting machinability. A precise determination of ADI microstructure, on the one hand, and to choose correct machining process parameters and tool wear control on the other, are essential to optimize cutting processes and for the introduction of ceramic inserts. Ceramics are an alternative to carbide tools. In this paper, ceramic tools for the dry turning of ADI castings are studied. Thus, different technical ceramics were analyzed, identifying the dominant wear mechanism and evolution. Tool wear rate magnitude was determined indirectly by the variation of cutting force along machining time. Finally, different tests helped to study ceramics wear sensitivity with respect to cutting parameters. Mixed ceramics of Al2O3 with TiC showed the best performance, followed by SiAlON ones.


Author(s):  
Amogh Arvind Shurpali ◽  
Emily Van Dam ◽  
J. Riley Edwards ◽  
David A. Lange ◽  
Christopher P. L. Barkan

Currently, there are divergent design and performance demands on railway infrastructure components due to increasing freight axle loads and cumulative gross tonnages, as well as increased investment in high-speed passenger rail development in North America. The divergence in loading and performance demands on shared infrastructure arises from the fact that while high-speed passenger trains exert lower loads at relatively high speeds, freight trains exert high loads at relatively low speeds. Improvements in infrastructure component designs are needed to achieve increased durability and tighter geometric tolerances. According to a rail industry survey administered by University of Illinois at Urbana-Champaign (UIUC) in 2008, Rail Seat Deterioration (RSD) is the principal performance problem limiting the service life of concrete crossties in North America. Rail infrastructure researchers and industry experts agree that abrasive wear may occur due to relative motion between the rail pad and concrete crosstie rail seat, potentially resulting in RSD. The complex tribological process of abrasion is further complicated and expected to be accelerated by the presence of abrasive fines and moisture, creating 3-body wear condition. Lack of understanding of the abrasion mechanism has resulted in a sub-optimal and iterative design of ties, causing reduced service life. This paper summarizes our efforts in understanding the effect of changing the mix design of concrete on the abrasion resistance of the rail seat which will eventually help us in modeling abrasive wear in RSD by constructing a mathematical relationship between the rail seat wear rate and input parameters including concrete mix design, mechanical/tribological properties of materials involved, normal load applied, presence of moisture, and abrasive fines. To simulate abrasive wear in RSD, a simple experiment is being carried out using a rotating wheel (lapping machine) capable of abrading concrete samples as a part of UIUC’s Small-Scale Abrasion Resistance Test (SSART). The objective of this research is to develop wear performance curves (e.g. wear depth versus load/time/cycles) for lab specimens developed from concrete crosstie mix designs that are currently being used in the industry, as well as for the evaluation of new mix designs. These data will help the rail industry in mechanistically designing concrete crossties by improving the understanding of materials used for concrete crosstie mix designs, with the objective of decreasing life cycle costs for the crosstie and fastening system. Preliminary SSART results are in agreement with relevant literature documenting the relationships between concrete mix designs and curing conditions and the resulting rate of abrasion.


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