Microstructure and Mechanical Properties of Austempered High Boron Cast Iron with Modification and its Mechanism Discussion

2013 ◽  
Vol 744 ◽  
pp. 349-352
Author(s):  
Xiao Hu ◽  
Xiang Chen ◽  
Yan Xiang Li
Keyword(s):  
Mechanical Properties ◽  
Cast Iron ◽  
Impact Toughness ◽  
Cast Alloy ◽  
Grain Refining ◽  
Small Particles ◽  
Microstructure And Mechanical Properties ◽  
High Boron ◽  
Austempering Temperature ◽  
The Impact

A kind of austempered boron alloyed high silicon cast alloy was developed though modification with Ti and controlling austempering temperature, the impact toughness of which increases to 20.7 J/cm2, which is more than triple that of the previous work. The alloy with modification exhibits obvious grain refining both in matrix and boride, improved the morphology of boride into discontinuous network and small particles. The phenomenon and mechanism are discussed in the article, it proved TiC is possible to act as the nuclei of eutectic boride and Ti can be an effective modifier.

The Effect of Modification and Heat Treatment on Low Chromium White Cast Iron

2011 ◽  
Vol 418-420 ◽  
pp. 1114-1117 ◽  
Author(s):  
E Liu ◽  
Feng Lan Wei ◽  
Li Chun Qiu
Keyword(s):  
Mechanical Properties ◽  
Heat Treatment ◽  
Cast Iron ◽  
Impact Toughness ◽  
White Cast Iron ◽  
Microstructure And Mechanical Properties ◽  
Carbide Morphology ◽  
The Impact ◽  
Compound Modification

The effect of compound modification and various kinds of heat treatment on microstructure and mechanical properties of the low chromium white cast iron was studied.The results showed that,after modification,the carbide morphology in cast iron has been greatly improved;the annealed modified cast iron is suitable for machining;both martensitic quenching and austempering can cause the hardness and the impact toughness of modified cast iron increase greatly.

scholarly journals Influence of Vanadium on the Microstructure and Mechanical Properties of Medium-Carbon Steels for Wheels

Metals ◽  
2018 ◽  
Vol 8 (12) ◽  
pp. 978 ◽  
Author(s):  
Pengfei Wang ◽  
Zhaodong Li ◽  
Guobiao Lin ◽  
Shitong Zhou ◽  
Caifu Yang ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Impact Toughness ◽  
Grain Refinement ◽  
Carbon Steels ◽  
Precipitation Strengthening ◽  
Austenite Grain Size ◽  
Medium Carbon ◽  
Microstructure And Mechanical Properties ◽  
Medium Carbon Steels ◽  
The Impact

Steels used for high-speed train wheels require a combination of high strength, toughness, and wear resistance. In 0.54% C-0.9% Si wheel steel, the addition of 0.075 or 0.12 wt % V can refine grains and increase the ferrite content and toughness, although the influence on the microstructure and toughness is complex and poorly understood. We investigated the effect of 0.03, 0.12, and 0.23 wt % V on the microstructure and mechanical properties of medium-carbon steels (0.54% C-0.9% Si) for train wheels. As the V content increased, the precipitation strengthening increased, whereas the grain refinement initially increased, and then it remained unchanged. The increase in strength and hardness was mainly due to V(C,N) precipitation strengthening. Increasing the V content to 0.12 wt % refined the austenite grain size and pearlite block size, and increased the density of high-angle ferrite boundaries and ferrite volume fraction. The grain refinement improved the impact toughness. However, the impact toughness then reduced as the V content was increased to 0.23 wt %, because grain refinement did not further increase, whereas precipitation strengthening and ferrite hardening occurred.

Effect of Tempering Time on Microstructure and Mechanical Properties of SA738 Gr.B Steel

2021 ◽  
Vol 1016 ◽  
pp. 1739-1746
Author(s):  
Yan Mei Li ◽  
Shu Zhan Zhang ◽  
Zai Wei Jiang ◽  
Sheng Yu ◽  
Qi Bin Ye ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Impact Toughness ◽  
Yield Strength ◽  
Microstructure Evolution ◽  
Impact Energy ◽  
Nuclear Power ◽  
Microstructure And Mechanical Properties ◽  
The Impact ◽  
Tempering Time

The effect of tempering time on the microstructure and mechanical properties of SA738 Gr.B nuclear power steel was studied using SEM, TEM and thermodynamic software, and its precipitation and microstructure evolution during tempering were clarified. The results showed that SA738 Gr.B nuclear power steel has better comprehensive mechanical properties after tempering at 650 °C for 1h. With the extension of the tempering time, M3C transformed into M23C6 with increasing size, which affected the yield strength and impact energy. When the tempering time is 8h ~ 10h, due to the transformation of M3C to M23C6, the composition of matrix around the carbide changed, causing the temperature of Ac1 dropped, forming twin-martensite which deteriorated the impact toughness of the steel.

scholarly journals MICROSTRUCTURE AND PROPERTIES OF HIGH CHROMIUM WHITE CAST IRONS ALLOYED WITH BORON

2021 ◽  
Vol 3 ◽  
pp. 137-141
Author(s):  
Julieta Kaleicheva ◽  
Krasimir Kirov ◽  
Valentin Plamenov Mishev ◽  
Zdravka Karaguiozova
Keyword(s):  
Mechanical Properties ◽  
Cast Iron ◽  
Impact Toughness ◽  
Boron Content ◽  
Bending Strength ◽  
White Cast Iron ◽  
Metallographic Analysis ◽  
Cast Irons ◽  
High Chromium ◽  
The Impact

The microstructure and mechanical properties of high chromium white cast iron with composition: 2,6÷3,4% C; 0,9÷1,1% Si; 0,8÷1,1% Mn; 1,0÷1,3% Mo; 12,3÷13,4% Cr, additionally doped with boron in an amount of 0,18% to 1,25% is investigated. The microstructure of six compositions of white cast irons is studied by means of an optical metallographic analysis - one without boron, and the others contain 0,18%; 0,23%; 0,59%; 0,96% and 1,25% boron. A test is performed to determine: hardness by the Rockwell method; microhardness; bending strength and impact toughness. It was found that at a boron content of 0,18%; 0,23% and 0,59%, the structure of white cast irons is subeutectic, with impact toughness in the range of 1,80÷1,52 J/cm2; with a boron content of 0,96%, the structure of white cast iron is close to the eutectic, with impact toughness 0,98 J/cm2 ; at a boron content of 1,25% the structure of white cast iron is supereutectic and the impact toughness decreases to 0,68 J/cm2. With a change in the boron content from 0,8% to 1,25%, the amount of carbide phase in the structure of white cast iron increases, which leads to an increase in hardness from 53 to 59 HRC. The highest bending strength (Rmi=660,85 MPa) was obtained in white cast irons with a boron content of 0,23%. 

The Effects of Austempering Temperature and Time on Mechanical Properties of Ductile Cast Iron Grade FCD450

2020 ◽  
Vol 856 ◽  
pp. 92-98
Author(s):  
Janthira Chantarach ◽  
Rungsinee Canyook
Keyword(s):  
Mechanical Properties ◽  
Cast Iron ◽  
Low Temperature ◽  
Impact Toughness ◽  
Ductile Cast Iron ◽  
X Ray Diffraction ◽  
X Ray ◽  
Different Temperatures ◽  
Austempering Temperature ◽  
Iron Grade

The purpose of the study was to inspect microstructure, mechanical properties and impact toughness of ductile cast iron grade FCD450 produced by austempering process. The study focused on austempering parameter, which effected impact toughness of material at low temperature. The FCD450 was initially temperature austenized at 885°C (1625˚F) for 2 hours. Austempering was carried out at three different temperatures of 271°C (520˚F), 313°C (560˚F) and 357°C (675˚F). The austempering temperature were varied at 1.5, 2.5 and 3.5 hours. X-ray diffraction was showed that the austempered ductile cast iron (ADI) microstructure consists of austenite and ferrite. The results showed that when austempered at 357°C (675˚F) for 2.5 hours has highest hardness and impact energy at low temperature. The dimple ductile fracture of ADI fracture surfaces was revealed by scanning electron microscope (SEM).

Influence of Mn and Heat Treatment Technology on Microstructure and Mechanical Properties of a Low-Alloy Wear-Resistant Cast Steel Shovel Tooth

2012 ◽  
Vol 557-559 ◽  
pp. 34-37
Author(s):  
Jing Qiang Zhang ◽  
Jie Min Du ◽  
Ji Wei Guo ◽  
Shou Fan Rong ◽  
Guang Zhou Wang
Keyword(s):  
Mechanical Properties ◽  
Heat Treatment ◽  
Impact Toughness ◽  
Cast Steel ◽  
Treatment Technology ◽  
Wear Resistant ◽  
Heat Treatment Technology ◽  
Microstructure And Mechanical Properties ◽  
Mn Content ◽  
The Impact

The influences of Mn and heat-treatment technology on microstructure and mechanical properties of medium-carbon-low-alloy wear-resistant cast steel were investigated. The results show that the hardness first increases and then drops down with the increase of Mn content, and the best hardness is 54HRC with Mn content 1.5%. The impact toughness first increases and then drops down with the increase of Mn content. The hardness and impact toughness first increase and then drop down with the increases of quenching temperature. The optimal impact toughness can be obtaind by quenching at 920°C and tempering at 200°C. Part of lower bainite and residual austenite and mass of tempered martensite are obtaind after tempering.

Microstructure and Mechanical Properties of Spray Deposited W9Mo3Cr4V High Speed Steel

2011 ◽  
Vol 391-392 ◽  
pp. 714-718
Author(s):  
Rui Zhou ◽  
Jian Fei Sun ◽  
Ying Jun Yang
Keyword(s):  
Mechanical Properties ◽  
Impact Toughness ◽  
High Speed ◽  
Bending Strength ◽  
Spray Deposition ◽  
High Speed Steel ◽  
Solidification Shrinkage ◽  
Microstructure And Mechanical Properties ◽  
The Matrix ◽  
The Impact

Microstructure and mechanical properties of W9Mo3Cr4V high speed steel fabricated by spray deposition have been studied. Spray deposited W9Mo3Cr4V high speed steel has a typical equiaxed structure which is finer and more homogeneous with a grain size of 20-30 micrometer compared with conventional casted counterparts. There are pores in the matrix of the deposited steel, which involve gas porosity, filling porosity and solidification shrinkage. As-deposited high speed steel is mainly composed of martensite, austenite and carbides which comprise MC carbide and M6C carbide. Mechanical properties show that the hardness and bending strength of the as-deposited steel are higher than that of the conventionally casted ones. However, impact toughness of the high speed steel is lower than that of the conventionally casted steel, which can be attributed to the existence of porosities and M6C carbides which reduce the impact toughness of high speed steels.

scholarly journals Effect of austempering temperature on microstructure and mechanical properties of ductile cast iron modified by niobium

2021 ◽  
Vol 12 ◽  
pp. 2414-2425
Author(s):  
Wilson Sckudlarek ◽  
Manar N. Krmasha ◽  
Kassim S. Al-Rubaie ◽  
Orlando Preti ◽  
Julio C.G. Milan ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Cast Iron ◽  
Ductile Cast Iron ◽  
Microstructure And Mechanical Properties ◽  
Austempering Temperature

The Effects of Heat Treatment on Microstructure and Mechanical Properties of AISI 4140 for Base Cutter Cane Harvester

2013 ◽  
Vol 774-776 ◽  
pp. 1059-1067 ◽  
Author(s):  
Wichan Chuaiphan ◽  
Loeshpahn Srijaroenpramong ◽  
Dumrongrit Pinpradub
Keyword(s):  
Mechanical Properties ◽  
Heat Treatment ◽  
Cast Iron ◽  
Impact Toughness ◽  
Retained Austenite ◽  
Quenching Condition ◽  
Microstructure And Mechanical Properties ◽  
Aisi 4140 ◽  
Air Medium ◽  
Tempering Process

The effects of heat treatment on microstructure and mechanical properties of AISI 4140 for base cutter cane harvester were studied. The effect of heat treatment - i.e. the different quenching medium (water, oil and air mediums) and the different heat treatment condition (quenching, quenching+tempering, cover scrap cast iron+ quenching and cover scrap cast iron+ quenching+tempering) on the on microstructure and mechanical properties (hardness, impact toughness and bend test). The material AISI 4140 was purchased from local market in Thailand and an emission spectroscopy was applied to quantify the amount of elements in steel. The specimens were heat treated in an induction furnace. The resultant microstructure of materials AISI 4140 consists of martensite and retained austenite after quenching all mediums, which quenching in water it have more than in oil and air medium respectively. The microstructure of materials AISI 4140 after tempering process consists of bainitic structure (ferrite and epsilon carbide) and retained austenite, which tempering in water quenching condition it have more than in oil and air quenching condition respectively. The hardness, impact toughness and bended test are according to behavior heat transfer of quenching mediums. The material alloy steel grade AISI 4140 is the good candidates to promote the quenching in water ,oil and air medium and must be continuous to tempering process. The technique heating by cover scrape cast iron it was good for protected surface and decreased decarburization on surface of steels. But it is not necessary for control microstructure and mechanical properties.

Sign in / Sign up

Export Citation Format

Share Document