scholarly journals ADI after Austenitising from Intercritical Temperature

2013 ◽  
Vol 13 (1) ◽  
pp. 81-88
Author(s):  
A. Kowalskia ◽  
S. Kluska-Nawarecka ◽  
K. Regulski
Keyword(s):  
Mechanical Properties ◽  
Heat Treatment ◽  
Fuzzy Logic ◽  
Cast Iron ◽  
Chemical Composition ◽  
Ductile Iron ◽  
Logic Model ◽  
Plastic Properties ◽  
The Matrix ◽  
Different Temperatures

Abstract ADI subjected to austenitising at intercritical temperatures contains in its matrix the precipitates of pre-eutectoid ferrite. Studies were carried out on the ductile iron of the following chemical composition: C = 3,80%, Si = 2,30%, Mn = 0,28%, P = 0,060%, S = 0,010%, Mg = 0,065%, Ni = 0,60%, Cu = 0,70%, Mo = 0,21% This cast iron was austenitised at three different temperatures, i.e. 800, 815 and 830oC and austempered at 360 and 380oC. For each variant of the cast iron heat treatment, the mechanical properties, i.e. YS, TS, EL and Hardness, were measured, and structure of the matrix was examined. Higher plastic properties were obtained owing to the presence of certain amount of pre-eutectoid ferrite. The properties were visualised using fuzzy logic model in a MATLAB. software.

scholarly journals Effect of Heat Treatment Parameters on the Toughness of Unalloyed Ausferritic Ductile Iron

2016 ◽  
Vol 16 (2) ◽  
pp. 79-84 ◽  
Author(s):  
E. Guzik ◽  
M. Sokolnicki ◽  
A. Nowak
Keyword(s):  
Mechanical Properties ◽  
Heat Treatment ◽  
Cast Iron ◽  
Ductile Iron ◽  
High Strength ◽  
Process Window ◽  
Austenitizing Temperature ◽  
Plastic Properties ◽  
Alloyed Cast Iron ◽  
Nodular Graphite

Abstract Studies were carried out to determine the effect of heat treatment parameters on the plastic properties of unalloyed ausferritic ductile iron, such as the elongation and toughness at ambient temperature and at – 60 °C. The effect of austenitizing temperature (850, 900 and 950°C) and ausferritizing time (5 - 180 min.) at a temperature of 360°C was also discussed. The next step covered investigations of a relationship that is believed to exist between the temperature (270, 300, 330, 360 and 390 °C) and time (5, 10, 30, 60, 90, 120, 150, 180, 240 min.) of the austempering treatment and the mechanical properties of unalloyed ausferritic ductile iron, when the austenitizing temperature is 950°C. The “process window” was calculated for the ADI characterized by high toughness corresponding to the EN-GJS-800-10-RT and EN-GJS-900-8 grades according to EN-PN 1564 and to other high-strength grades included in this standard. Low-alloyed cast iron with the nodular graphite is an excellent starting material for the technological design of all the ausferritic ductile iron grades included in the PN-EN-1624 standard. The examined cast iron is characterized by high mechanical properties stable within the entire range of heat treatment parameters.

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 Effect of Heat-treatment Parameters of Cast Iron GJS-X350NiMnCu7-3-2 on its Structure and Mechanical Properties

2017 ◽  
Vol 17 (1) ◽  
pp. 121-126 ◽  
Author(s):  
D. Medyński ◽  
A. Janus ◽  
S. Zaborski
Keyword(s):  
Mechanical Properties ◽  
Heat Treatment ◽  
Tensile Strength ◽  
Cast Iron ◽  
High Hardness ◽  
Spheroidal Graphite ◽  
Air Cooling ◽  
Material Hardness ◽  
The Matrix ◽  
Lower Material

Abstract The paper presents influence of soaking parameters (temperature and time) on structure and mechanical properties of spheroidal graphite nickel-manganese-copper cast iron, containing: 7.2% Ni, 2.6% Mn and 2.4% Cu. Raw castings showed austenitic structure and relatively low hardness (150 HBW) guaranteeing their good machinability. Heat treatment consisted in soaking the castings within 400 to 600°C for 2 to 10 hours followed by air-cooling. In most cases, soaking caused changes in structure and, in consequence, an increase of hardness in comparison to raw castings. The highest hardness and tensile strength was obtained after soaking at 550°C for 6 hours. At the same time, decrease of the parameters related to plasticity of cast iron (elongation and impact strength) was observed. This resulted from the fact that, in these conditions, the largest fraction of fine-acicular ferrite with relatively high hardness (490 HV0.1) was created in the matrix. At lower temperatures and after shorter soaking times, hardness and tensile strength were lower because of smaller degree of austenite transformation. At higher temperatures and after longer soaking times, fine-dispersive ferrite was produced. That resulted in slightly lower material hardness.

Enhancement of the Gray Cast Iron Properties by Adding Chromium Element

2017 ◽  
Vol 753 ◽  
pp. 218-221
Author(s):  
Awad Eisa Gaib Alla Mohamed ◽  
Khairi Abdulsalam
Keyword(s):  
Mechanical Properties ◽  
Heat Treatment ◽  
Cast Iron ◽  
Gray Cast Iron ◽  
Chromium Content ◽  
Gray Cast ◽  
Three Samples ◽  
Before And After ◽  
Different Temperatures

In this paper the effect of chromium element on some mechanical properties of gray cast iron is studied .The work was divided in to four categories, each category has three samples; each sample has three different chromium content 0.0%, 1.7%, 3.7%. The mechanical properties were investigated (hardness and impact) before and after the heat treatment. The heat treatment was carried out for period of 12 minutes at two different temperatures. The results confirmed that durability, toughness, and hardness are proportional to the chromium content. The ultimate aim of this research is to enhance the mechanical properties of gray cast iron by adding chromium element.

scholarly journals Research and Analysis of the Effect of Heat Treatment on Damping Properties of Ductile Iron

Open Physics ◽  
2019 ◽  
Vol 17 (1) ◽  
pp. 566-574
Author(s):  
Yu Zhang ◽  
Erjun Guo ◽  
Liping Wang ◽  
Yicheng Feng ◽  
Sicong Zhao ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Heat Treatment ◽  
Wear Resistance ◽  
Cast Iron ◽  
Ductile Iron ◽  
Cast Steel ◽  
High Stress ◽  
High Strength ◽  
Spheroidal Graphite ◽  
High Plasticity

Abstract With the continuous development of metal manufacturing technology, high-strength and high-hardness ductile iron materials have excellent comprehensive performance. Many performance indexes are comparable to those of alloy steels, and they have excellent casting properties. Many large-scale parts produced by cast steel are slowly being replaced by this material. Ductile iron is obtained by a spheroidizing treatment and inoculation to obtain spheroidal graphite. The mechanical properties of cast iron have been effectively improved, especially plasticity and toughness, and the strength obtained is higher than that of carbon steel. Ductile iron has the properties of iron and the properties of steel. It is a new type of engineering material with high plasticity, strength, corrosion resistance, and wear-resistance. Because of its excellent performance, it has been successfully used to cast parts with high-stress conditions, high strength, toughness and wear resistance. Due to the small splitting effect of ductile iron on the metal matrix, the stress concentration is effectively eliminated. Therefore, the matrix structure of ductile cast iron is changed by heat treatment, thereby improving its mechanical properties and the damping performance of the material itself. Through a heat treatment process experiment of ductile iron, the related process and technical measures of damping performance in the heat treatment production process are obtained.

6XXX Alloys: Chemical Composition and Heat Treatment

2019 ◽  
Author(s):  
Grażyna Mrówka-Nowotnik
Keyword(s):  
Mechanical Properties ◽  
Heat Treatment ◽  
Chemical Composition ◽  
Intermetallic Phase ◽  
Chinese Script ◽  
High Dispersion ◽  
Cu Content ◽  
The Matrix ◽  
Si Content ◽  
Additional Phase

Analysis of the influence of chemical composition, crystallization process and heat treatment on the phase constituents’ morphology, and mechanical properties and crack resistance of 6xxx Al alloys were conducted. The alloys with low Mg and Si content (6063) in the as-cast state are characterized by presence of Si particles and primary intermetallic phases: α-Al8Fe2Si, β-Al5FeSi, β-Mg2Si, and α-Al(FeMn)Si. Higher Mg, Si, and Mn content (6005 and 6082) leads to separation of additional phase particles: Al6Fe, Al6Mn, and Al12(FeMn)Mg3Si6, whereas high Cu content (6061—0.35% and 6066—0.95%, respectively) is responsible for precipitation of additional phase particles: Q-Al5Cu2Mg8Si6 and θ-Al2Cu. It has been established that homogenization results in total dissolution of the θ-Al2Cu and Q-Al5Cu2Mg8Si6 primary phases and partial dissolution of β-Mg2Si. Needle-like and Chinese-script α-Al8Fe2Si and β-Al5FeSi were transformed into spheroidal α-Al(FeMn)Si particles. The maximal consolidation of the 6xxx alloys is a result of precipitation of metastable particles, the transient βʺ, βʹ, and Qʹ/θʹ phases (6061 alloy) with high dispersion. The highest mechanical properties were achieved after holding in the temperature of 565°C/6 h, supersaturated in water, and aging at 175°C/10–20 h (T6). The decohesion process in the presence of tensile stresses in the room temperature proceeds through nucleation, the growth and joining of the voids, as well as the cracking of the primary and secondary large-sized intermetallic phase particles. The increase of deformation temperature up to 300°C causes the changes of the nucleation source and joining of voids—it occurs mainly along the matrix–particle interface.

Mechanical Properties of Tempered Ti-Nb Alloyed Ductile Iron

2013 ◽  
Vol 393 ◽  
pp. 126-129
Author(s):  
Bulan Abdullah ◽  
Siti Khadijah Alias ◽  
Ahmed Jaffar ◽  
Abdul Hakim Abdullah ◽  
Syazuan Abdul Latip ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Heat Treatment ◽  
Ductile Iron ◽  
Casting Process ◽  
Xrd Analysis ◽  
Tempering Temperature ◽  
Microstructure Observation ◽  
Different Temperatures ◽  
Process Heat ◽  
And Performance

The applications of ductile iron in numerous engineering applications require continuous effort in properties enhancement due to the necessity of product sustainability and performance. The studies highlighted the effect of 0.5 wt% titanium and niobium addition the mechanical properties of tempered ductile iron. The samples were prepared through conventional CO2 sand casting process. Heat treatment was conducted by austenitizing at 900°C for 1 hour and subsequently oil quenching before tempered at three different temperatures which are 500°C, 600°C and 700°C at 1 hour holding time. The mechanical properties were evaluated through impact (ASTM E23) and hardness (Rockwell) test. Microstructure observation and XRD analysis was also performed on as cast and tempered samples. The findings indicated that increasing the tempering temperature at 700°C enhanced the hardness and tensile strength of tempered alloyed ductile iron compared to other samples. The enhancement of the mechanical properties of tempered alloyed ductile iron is expected to further expand the applications of ductile iron.

Multiple inoculations of ductile iron and the effects on properties

2015 ◽  
Vol 4 (4) ◽  
pp. 526
Author(s):  
Adebayo Badmos ◽  
Kelvin Fakehinde
Keyword(s):  
Mechanical Properties ◽  
Cast Iron ◽  
Ductile Iron ◽  
Primary Inoculation ◽  
The Matrix

Multiple inoculation of ductile iron and the effects on the structure and mechanical properties have being investigated. Samples of ductile iron were produced with inoculation carried out either once or twice and with different materials as inoculants. Ferrosilicon was used for the primary inoculation and either ferrosilicon or nickel-ferrosilicon for the secondary inoculation. It is observed that the nodules produced are more and finer with multiple inoculations and the effect is more pronounced with nickel-ferrosilicon as the secondary inoculant. Multiple inoculations produce an increase in the hardness of ductile iron when ferrosilicon is used as the secondary inoculant while a decrease in the hardness is observed with nickel-ferrosilicon despite the finer nodules. This is explained by the fact that nickel enhances graphitization in cast iron thereby depleting carbon in the matrix and making the cast iron weaker but with more nodules.

Effect of Two-Cycle Heat Treatment on Mechanical Properties of Ductile Iron

2013 ◽  
Vol 393 ◽  
pp. 79-82
Author(s):  
B. Abdullah ◽  
Mohd Faizul Idham ◽  
A. Jaffar ◽  
Ahmad Faiz Zubair ◽  
M. Mohamed
Keyword(s):  
Mechanical Properties ◽  
Heat Treatment ◽  
Ductile Iron ◽  
Treatment Process ◽  
Treatment Processes ◽  
Hardness Tests ◽  
Heat Treated ◽  
Different Temperatures ◽  
Two Stages ◽  
Holding Temperature

The aim of this study is to investigate the mechanical properties of ductile iron after treatment with two-cycle heat treatment processes which modified from austempering. The modified heat treatments have two stages holding temperature. Ductile iron was austenitized at 900 °C for an hour and followed by transferring the sample to other furnace which was set at different temperatures of i) 250 °C; ii) 300 °C; iii) 350 °C without quenching for 1.5 hours. Tensile (ASTM E8M), impact (ASTM-E23-1990) and Rockwell hardness tests were carried out to study the mechanical properties of the ductile iron. It was found that the sample which was heat treated using two-cycle heat treatment process at temperature of 250 °C contributed to better absorbing impact energy properties and hardness properties. Meanwhile, sample that heat treated at 350 °C has higher tensile strength.

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