Properties and Structure of High-Silicone Austempered Ductile Iron

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.

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Effect of Phenomena Accompanying Wear in Dry Corundum Abrasive on the Properties and Microstructure of Austempered Ductile Iron with Different Chemical Composition

Archives of Metallurgy and Materials ◽

10.1515/amm-2015-0078 ◽

2015 ◽

Vol 60 (1) ◽

pp. 483-490 ◽

Cited By ~ 1

Author(s):

D. Myszka ◽

A. Wieczorek

Keyword(s):

Mechanical Properties ◽

Wear Resistance ◽

Ductile Iron ◽

Surface Hardening ◽

The Other ◽

Austempered Ductile Iron ◽

High Wear Resistance ◽

New Materials ◽

Heat Treated ◽

Mining Machinery

Abstract The research described in this article is a fragment in the series of published works trying to determine the applicability of new materials for parts of the mining machinery. Tests were performed on two groups of austempered ductile iron - one of which contained 1.5% Ni and 0.5% Mo, while the other contained 1.9% Ni and 0.9% Cu. Each group has been heat treated according to the three different heat treatment variants and then the material was subjected to detailed testing of mechanical properties and abrasion wear resistance, measuring also hardness and magnetic properties, and conducting microstructural examinations. The results indicated that each of the tested materials was senstive to the surface hardening effect, which resulted in high wear resistance. It has been found that high temperature of austempering, i.e. 370°C, favours high wear resistance of ductile iron containing nickel and molybdenum. Low temperature of austempering, i.e. 270°C, develops high wear resistance in ductile iron containing nickel and copper. Both these materials offer completely different mechanical properties and as such can be used for different and specific applications.

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Abrasive wear of ploughshare blades made of Austempered Ductile Iron

Acta Universitatis Agriculturae et Silviculturae Mendelianae Brunensis ◽

10.11118/actaun200755010173 ◽

2007 ◽

Vol 55 (1) ◽

pp. 173-182 ◽

Cited By ~ 5

Author(s):

Jiří Votava ◽

Michal Černý ◽

J. Filípek

Keyword(s):

Cast Iron ◽

Abrasive Wear ◽

Ductile Iron ◽

Base Material ◽

Field Tests ◽

Nodular Cast Iron ◽

Austempered Ductile Iron ◽

Spheroidal Graphite ◽

Cast State ◽

Heat Treated

The objective of this article consists in exhaustive monitoring of abrasive wear and subsequent evaluation of nodular cast iron with spheroidal graphite used as the base material for production of ploughshare blades. Nodular cast iron has a lot of convenient properties for production of these components. We have tested this material in field tests. For these tests there were manufactured ploughshare blades (directly according to original). These ploughshare blades were tested in practical conditions of agricultural company Farma Nedvězí Ltd. Three ploughshare blades were used in natural cast state and the others were heat-treated. During the test there were measured decreases of weights of the ploughshare blades and subsequently compared with decreases of original ploughshare blades, produced by company Opall Agri which are ordinarily available at our market.

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AUSTEMPERING HEAT TREATMENT STUDY OF CAST DUCTILE IRON: ANALYSIS OF MECHANICAL AND MICROSTRUCTURAL PROPERTIES, ACCORDING TO THE A897M STANDARD SPECIFICATIONS FOR AUSTEMPERED DUCTILE IRON CASTINGS

Periódico Tchê Química ◽

10.52571/ptq.v15.n29.2018.64_periodico29_pgs_64_74.pdf ◽

2018 ◽

Vol 15 (29) ◽

pp. 64-74

Author(s):

A. R. M. SCHIFINO ◽

F. R. SANTANNA ◽

A. P. TRINDADE

Keyword(s):

Mechanical Properties ◽

Heat Treatment ◽

Cast Iron ◽

Ductile Iron ◽

Great Influence ◽

Metallic Matrix ◽

Nodular Cast Iron ◽

Austempered Ductile Iron ◽

Mechanical Resistance ◽

Spring Support

The objective of this work was to develop heat treatment parameters of an austempered cast iron alloy ASTM 897 / A 897M - 1400/1100/1, aiming at the production of a truck spring support. The austempered nodular cast iron, known by the acronym ADI - Austempered Ductile Iron - is a class of nodular cast iron that, after austempered thermal treatment, increases significantly its mechanical properties and tenacity (Machado, 2007). Mechanical and metallographic tests demonstrated the great influence that the level of microshrinkage has on the elongation and mechanical resistance of the material. Generally, tensile tests demonstrate high elongation due to minimal presence of microshrinkage and segregations in the metallic matrix of the material, as well as to the presence of austenite with high carbon retained in the ADI matrix. Analyzes were performed to determine if the mechanical properties required by ASTM 897 / A897M were achieved. Within this standard, four degrees can be obtained. The degree of interest in this study was 1400/1100/1, which is the grade requested by the company, so that the truck spring support can be put into service. Tensile, Charpy and optical microscopy tests were carried out.

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Influence of the Salt Bath Agitation and Austempering Temperature on the Microstructure of Austempered Ductile Iron

10.20944/preprints201710.0090.v1 ◽

2017 ◽

Author(s):

Nikša Čatipović ◽

Dražen Živković ◽

Zvonimir Dadić ◽

Marin Viceić

Keyword(s):

Mechanical Properties ◽

Heat Treatment ◽

Ductile Iron ◽

Salt Bath ◽

Austempered Ductile Iron ◽

Toughness Test ◽

Microstructure And Mechanical Properties ◽

Heat Treated ◽

Final Microstructure ◽

Austempering Temperature

In this paper the influence of austempering temperature and salt bath agitation on the final microstructure and mechanical properties of the ferritic ductile iron were studied. 17 samples had been subjected to different heat treatment parameters. Different microstructures were recorded upon the completion of the tests. From the obtained micro images, it is obvious that both the austempering temperature and salt bath agitation affect the final microstructure of the austempered ductile iron. Lower austempering temperatures and salt bath agitation produce more ausferrite in the microstructure, hence the harder and tougher phases are present. This was confirmed with hardness and toughness test of the 17 heat-treated samples. Lower austempering temperatures give more ausferrite phase and therefore higher hardness, but hardness decreases with increasing austempering temperatures. Toughness rises with rising austempering temperatures, but drops significantly with temperatures above 395°C because of the final microstructure.

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Effect of Cr content on microstructure and mechanical properties of carbidic austempered ductile iron

Materials Testing ◽

10.3139/120.111114 ◽

2018 ◽

Vol 60 (1) ◽

pp. 31-39 ◽

Cited By ~ 8

Author(s):

Haiqiang Cheng ◽

Hanguang Fu ◽

Jian Lin ◽

Yongping Lei

Keyword(s):

Mechanical Properties ◽

Ductile Iron ◽

Austempered Ductile Iron ◽

Cr Content ◽

Microstructure And Mechanical Properties

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Influence of Post Weld Heat Treatment on the Grain Size, and Mechanical Properties of the Alloy-800H Rotary Friction Weld Joints

Materials ◽

10.3390/ma14164366 ◽

2021 ◽

Vol 14 (16) ◽

pp. 4366

Author(s):

Saqib Anwar ◽

Ateekh Ur Rehman ◽

Yusuf Usmani ◽

Ali M. Al-Samhan

Keyword(s):

Mechanical Properties ◽

Heat Treatment ◽

Grain Size ◽

Heat Affected Zone ◽

Tensile Testing ◽

Weld Zone ◽

Alloy 800H ◽

Weld Joints ◽

Heat Treated ◽

Friction Weld

This study evaluated the microstructure, grain size, and mechanical properties of the alloy 800H rotary friction welds in as-welded and post-weld heat-treated conditions. The standards for the alloy 800H not only specify the composition and mechanical properties but also the minimum grain sizes. This is because these alloys are mostly used in creep resisting applications. The dynamic recrystallization of the highly strained and plasticized material during friction welding resulted in the fine grain structure (20 ± 2 µm) in the weld zone. However, a small increase in grain size was observed in the heat-affected zone of the weldment with a slight decrease in hardness compared to the base metal. Post-weld solution heat treatment (PWHT) of the friction weld joints increased the grain size (42 ± 4 µm) in the weld zone. Both as-welded and post-weld solution heat-treated friction weld joints failed in the heat-affected zone during the room temperature tensile testing and showed a lower yield strength and ultimate tensile strength than the base metal. A fracture analysis of the failed tensile samples revealed ductile fracture features. However, in high-temperature tensile testing, post-weld solution heat-treated joints exhibited superior elongation and strength compared to the as-welded joints due to the increase in the grain size of the weld metal. It was demonstrated in this study that the minimum grain size requirement of the alloy 800H friction weld joints could be successfully met by PWHT with improved strength and elongation, especially at high temperatures.

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