scholarly journals Mechanism of Damage of Ferritic Ductile Iron, Influence of Matrix Heterogeneity

2018 ◽  
Vol 925 ◽  
pp. 288-295 ◽  
Author(s):  
Diego O. Fernandino ◽  
Roberto Enrique Boeri ◽  
Juan M. Massone
Keyword(s):  
Mechanical Properties ◽  
Ductile Iron ◽  
Computational Modelling ◽  
Metallic Matrix ◽  
Ductile Cast Iron ◽  
Uniaxial Tensile ◽  
Damage Mechanisms ◽  
Ferritic Matrix ◽  
Micro Scale

Ferritic ductile cast iron (FDI) microstructure is composed by graphite nodules embedded in a ferritic matrix. It is usual to assume that the ferritic matrix is homogeneous. However, the experimental analysis shows impurities and in some cases a high degree of heterogeneity. It is necessary to investigate the influence of these heterogeneities on the mechanical properties of FDI.This work focusses on the characterization of the elastoplastic properties of different zones of the ferritic matrix of FDI and the identification of the sequence and extent of the damage mechanisms at the micro-scale under uniaxial tensile loading.The methodologies for the characterization of the material micro constituents and micro-segregated zones involve nano-indentation and atomic force microscopy techniques in combination with computational modelling. The analysis is performed by applying inverse analysis algorithms proposed in the literature. The microsegregated zones are identified by using color etching. The assessment of the micro-scale damage mechanisms was performed by in-situ optical microscopy observation of tensile tests of very small specimens.The results led to the quantification of the differences in mechanical properties along the metallic matrix as a result of the existing heterogeneities and allow for a better understanding of the ductile iron damage mechanism.

Characterization of Fusion Lines Obtained with Laser Welding on Ductile Iron Plates

2016 ◽  
Vol 254 ◽  
pp. 33-42
Author(s):  
Ioan Catalin Mon ◽  
Mircea Horia Tierean ◽  
Eugen Cicala ◽  
Michel Pilloz ◽  
Iryna Tomashchuk ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Laser Welding ◽  
Welding Speed ◽  
Ductile Iron ◽  
Continuous Laser ◽  
Welding Defects ◽  
Criteria For Selection ◽  
Selection Of ◽  
Melted Metal

This paper studies the ductile iron (DI) weldability using laser welding. For performing an Yb:YAG continuous laser was used, with a maximum power of 6 kW. The parametrical window power (P) - welding speed (S) was explored by carrying out the fusion lines on ductile iron plates without preheating, to determinate areas of weldability (complete penetration, correct geometry) to allow further characterization. The criteria for selection of focus areas were the geometry of the fusion lines and the absence of the welding defects. The unsatisfactory domains were characterized by: collapse of the melted metal, incomplete penetration, low fusion lines quality (geometry, compactness). In present study, several values of power and welding speed have been tested to identify their influence on geometry, compactness of the joints and mechanical properties. As result, the power-welding speed diagram for feasible domains of laser welding was generated.

Mechanical Characterization of Polymer Nanowires Using MEMS

2006 ◽  
Author(s):  
B. A. Samuel ◽  
Bo Yi ◽  
R. Rajagopalan ◽  
H. C. Foley ◽  
M. A. Haque
Keyword(s):  
Mechanical Properties ◽  
Tensile Testing ◽  
Furfuryl Alcohol ◽  
Mechanical Characterization ◽  
Uniaxial Tensile ◽  
Testing Device ◽  
Uniaxial Tensile Testing ◽  
Polymer Nanowires

We present results on the mechanical properties of single freestanding poly-furfuryl alcohol (PFA) nanowires (aspect ratio > 50, diameters 100–300 nm) from experiments conducted using a MEMS-based uniaxial tensile testing device in-situ inside the SEM. The specimens tested were pyrolyzed PFA nanowires (pyrolyzed at 800° C).

Influence of Charge Composition on EN-GJS-500-7 Ductile Iron Properties in Foundry Operating Conditions

2020 ◽  
Vol 998 ◽  
pp. 42-47
Author(s):  
Alena Pribulová ◽  
Peter Futaš ◽  
Marcela Pokusova
Keyword(s):  
Mechanical Properties ◽  
Cast Iron ◽  
Ductile Iron ◽  
Ductile Cast Iron ◽  
Operating Conditions ◽  
Production Costs ◽  
Steel Scrap ◽  
Charge Composition ◽  
Iron Castings ◽  
Worldwide Production

Worldwide production of ductile iron castings reached in year 2017 26,428,148 metric tons, which is 34% of the total weight of all castings made from cast iron. The most significant increase in ductile iron castings was recorded in Slovakia, up to 78.6%. Castings from ductile iron have a very huge utilization thanks their very good foundry and mechanical properties. The current economic situation in all industries forces entrepreneurs and producers to rationalize production and reduce production costs, with a worldwide trend to increase the share of steel scrap, a technology for the production of ductile cast iron. The paper describes the results of research focused on the effect of charge composition, mainly the share of scrap steel on the final properties and structure of ductile iron EN-GJS-500-7 under the operating conditions of foundry. Six melts with different charge composition were made. The samples from all melts were taken and chemical analysis, microstructure analysis and testing on mechanical properties were made on them. The mechanical properties of produced globular cast irons were according with the relevant standard. It is important to mention that there has been a significant increase in strength characteristics in melts in which the carbon content exceeded 4% (CE = 4.7 and 4.8%, respectively).

scholarly journals Effect of Processing Parameters on the Mechanical Properties of Heavy Section Ductile Iron

2015 ◽  
Vol 2015 ◽  
pp. 1-11 ◽  
Author(s):  
Mohamed Mahmoud Mourad ◽  
Shimaa El-Hadad ◽  
Mervat Mohamed Ibrahim ◽  
Adel Abdelmonem Nofal
Keyword(s):  
Mechanical Properties ◽  
Ductile Iron ◽  
Processing Parameters ◽  
Ductile Cast Iron ◽  
Heavy Section ◽  
The Matrix ◽  
Cast Alloys ◽  
One Step ◽  
Inoculation Procedure ◽  
Inoculation Treatment

The main objective of the current work is to investigate the influence of different inoculation conditions on the microstructure and mechanical properties of heavy section ductile iron (DI) castings. Inoculation treatment was done via one step and double step treatments with different amounts of inoculants. The mechanical properties of the fabricated samples were evaluated. The best inoculation procedure in terms of graphite nodules characteristics and mechanical properties was double inoculation with 0.8% inoculants added at first and 0.2% in the late inoculation step. The presence of Sb in one of the cast alloys controlled the growth of graphite nodules in these heavy section ductile iron castings; however low impact toughness was recorded. The matrix structure of ductile cast iron showed a significant influence not only on the strength and impact properties but also on the fracture mode during testing.

The Influence of Boron on Structure and Mechanical Properties of Bainite Ductile Iron in the Step Austempering in Room Temperature Machine Oil

2010 ◽  
Vol 139-141 ◽  
pp. 235-238
Author(s):  
De Qiang Wei
Keyword(s):  
Mechanical Properties ◽  
Heat Treatment ◽  
Cast Iron ◽  
Impact Strength ◽  
Ductile Iron ◽  
Room Temperature ◽  
Solute Drag ◽  
Ductile Cast Iron ◽  
Treatment Technique ◽  
The Impact

In this paper, the low alloy bainite ductile cast iron has been obtained by a new heat treatment technique of the step austempering in room-temperature machine oil. The effects of element boron, manganese and copper on structure and mechanical properties of the bainite ductile cast Iron in above-mentioned process are investigated. The phenomenon, hardness lag of the alloyed bainite ductile cast Iron, has been discussed. It shows that after the step austempering in room-temperature machine oil, the hardness will increases with the time. It is found that boron and manganese can increase the hardness and reduce the impact strength while copper can increase the impact strength. The results show that reasonable alloyed elements can improve mechanical properties of the bainite ductile cast Iron. Essentially, hardness lag of the alloyed bainite ductile cast Iron is resulted from solute drag-like effect.

scholarly journals Investigation of the Nodularisation Propensity of Calcined Cashew-Nut Shell-Ash in Cast-Iron Melt Graphite

2021 ◽  
Vol 18 (1) ◽  
pp. 1-8
Author(s):  
O.I. Sekunowo ◽  
J.O. Ugboaja ◽  
J.A. Tiamiyu
Keyword(s):  
Mechanical Properties ◽  
Cast Iron ◽  
Ductile Iron ◽  
Microstructural Analysis ◽  
Ductile Cast Iron ◽  
Cashew Nut ◽  
Melt Treatment ◽  
Master Alloys ◽  
Molten Cast Iron ◽  
Cashew Nut Shell

Production of ductile iron using ferrosilicon-magnesium master alloy in melt treatment is currently fraught with challenges bothering on cost and availability. In this study the suitability of cashew nut shells ash (CNSA) as a viable alternative to magnesium master alloys employed in the treatment of molten cast iron for enhanced mechanical properties was studied. The carbonized CNSA used varied from 2-10 wt. % to treat different heat batches; CA1-CA5 containing varied amount of CNSA, CaO and FeSi in the molten cast iron. The cast samples were subjected to both mechanical characterisation (tensile, hardness and impact) and microstructural analysis using Instron electromechanical machine, impact tester and scanning electron microscope (SEM) coupled with energy dispersive spectroscope (EDS). Results show that the 8 wt. % CNSA addition demonstrated the best mechanical properties comparable to ASTM A536 ferritic ductile cast iron. Specifically, the 8 wt. % CNSA cast samples exhibited 433 MPa tensile strength, 144HRC hardness and ductility of 14.7%. Contributions to improved mechanical properties may be attributed to the development of sufficient fractions of graphite nodules during melt treatment with CNSA. These outcomes are a boost both to the production of quality ductile irons and a cleaner environment. Keywords: Nodularisation, ductile-iron, cashew-nut, ferrosilicon-magnesium alloy, mechanical properties

scholarly journals Properties and Structure of High-Silicone Austempered Ductile Iron

2014 ◽  
Vol 14 (2) ◽  
pp. 91-94 ◽  
Author(s):  
A. Krzyńska ◽  
A. Kochański
Keyword(s):  
Mechanical Properties ◽  
Cast Iron ◽  
Ductile Iron ◽  
Tensile Testing ◽  
Hardness Measurement ◽  
Austempered Ductile Iron ◽  
Ferritic Matrix ◽  
Heat Treated

Abstract The results presented in this paper are a continuation of the previously published studies. The results of hest treatment of ductile iron with content 3,66%Si and 3,80% Si were produced. The experimental castings were subjected to austempering process for time 30, 60 and 90 minutes at temperature 300°C. The mechanical properties of heat treated specimens were studied using tensile testing and hardness measurement, while microstructures were evaluated with conventional metallographic observations. It was again stated that austempering of high silicone ferritic matrix ductile iron allowed producing ADI-type cast iron with mechanical properties comparable with standard ADI.

scholarly journals Properties investigation of austempered ductile iron

10.30544/137 ◽  
2016 ◽  
Vol 22 (1) ◽  
pp. 25-30
Author(s):  
Sudhanshu Detwal ◽  
Deivanathan R
Keyword(s):  
Mechanical Properties ◽  
Ductile Iron ◽  
Heat Treatments ◽  
Ductile Cast Iron ◽  
Casting Technique ◽  
Different Temperatures ◽  
Sand Mould ◽  
Austempering Temperature ◽  
Iron Material ◽  
Mould Casting

This work concerns microstructural and mechanical properties of an austempered ductile cast iron (ADI). The ductile iron material was produced by the sand mould casting technique. Afterwards, austempering heat treatment was applied to the specimens at two different temperatures of 250°C and 350°C. Austempered Ductile Irons (ADIs) were produced successfully by different two-stage heat treatments, to obtain favorable microstructure and hardness. The microstructure and hardness obtained by such variable heat treatments were compared. The austempering temperature and time were found to be decisive parameters in obtaining a desired ADI microstructure.

TENSILE CHARACTERIZATION OF TEXTILE REINFORCED MORTAR

2017 ◽  
Vol 4 (1) ◽  
Author(s):  
Adel Younis ◽  
Usama Ebead ◽  
Kshitij Shrestha
Keyword(s):  
Mechanical Properties ◽  
Tensile Load ◽  
Constitutive Law ◽  
Uniaxial Tensile ◽  
Textile Materials ◽  
Study Results ◽  
Tensile Characterization ◽  
Textile Reinforced Mortar ◽  
Common Shape

Textile reinforced mortar (TRM) is a composite material consisting of dry fibers embedded in a cementitious matrix, commonly used for strengthening masonry and concrete structures. In general, tensile characterization is required to identify the TRM mechanical properties, which are considered the key parameters needed for the structural design of strengthening systems. This paper presents the results of an experimental study conducted to investigate the tensile properties of TRM. In this effort, a total of 15 TRM coupons of 410 mm in length, 50 mm in width, and 10 mm in thickness were tested under uniaxial tensile load with clevis-type anchors. Three different types of textile materials were considered: carbon, glass, and polyparaphenylene benzobisoxazole (PBO). As for the study results, a common shape of the TRM tensile constitutive law was observed. Moreover, the average mechanical properties were listed for each type of TRM. Finally, the results and considerations presented in this work can enrich the literature with background data, which are beneficial for future applications of TRM systems in structural rehabilitation and repair.

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