Effect of High Carbon Content in the Filler Metal on Room Temperature and High Temperature Mechanical Properties of Low Alloy Ferritic Cr-Mo-V Steel Weldments

Inconel 713C alloy was tried to manufacture by using MIM(Metal Injection Molding) process. The high-temperature mechanical properties of MIMed Inconel 713C were also investigated. Processing defects such as pores and binders could be observed near the surface. Tensile tests were conducted from room temperature to 900°C. The result of tensile tests showed that this alloy had similar or somewhat higher strengths (YS: 734 MPa, UTS: 968 MPa, elongation: 7.16 % at room temperature) from RT to 700°C than those of conventional Inconel 713C alloys. Above 800°C, however, ultimate tensile strength decreased rapidly with increasing temperature (lower than casted Inconel 713C). Based on the observation of fractography, initial crack was found to have started near the surface defects and propagated rapidly. The superior mechanical properties of MIMed Inconel 713C could be obtained by optimizing the MIM process parameters.

Download Full-text

The Influence on High-Temperature Mechanical Properties of Hybrid-Fiber-Reinforced High-Performance Concrete and Microscopic Analysis

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.226-228.1709 ◽

2012 ◽

Vol 226-228 ◽

pp. 1709-1713

Author(s):

Lan Yan ◽

Y.M. Xing ◽

Ji Jun Li

Keyword(s):

Mechanical Properties ◽

High Temperature ◽

Transition Zone ◽

High Performance ◽

Room Temperature ◽

Steel Fiber ◽

High Performance Concrete ◽

Interfacial Transition Zone ◽

Hybrid Fiber ◽

High Temperature Mechanical Properties

This paper investigated the high temperature mechanical properties of the hybrid fiber reinforced high performance concrete (HFHPC) and normal concrete (NC) .After being subjected to different elevated heating temperatures, two kinds of concretes have been tested for the compressive strength, splitting tensile strength and flexural strength of test specimen at room temperature and 200 °C,400 °C,600 °C,800 °C.Microstructure changes of concrete were also observed by using Scanning Electron Microscopy (SEM) after high temperature. The results show that the hybrid fiber can significantly increase mechanical properties of the concrete at room temperature and high temperature. SEM and XRD analysis shows that there is a permeable diffusion layer in the steel fiber surface because of solid state reaction in the Interfacial Transition Zone of steel fiber and concrete. This permeable diffusion layer is white, bright, serrated and mainly consist of FeSi2 and the complex hydrated calcium silicate. The compounds of this layer change the Interfacial Transition Zone structure, enhance bonding capacity of the steel fiber and matrix, and increase the high temperature mechanical properties of concrete.

Download Full-text

Tailoring Carbon Nanoclusters to Desired Morphologies

Journal of Materials Research ◽

10.1557/jmr.1998.0339 ◽

1998 ◽

Vol 13 (9) ◽

pp. 2438-2444 ◽

Cited By ~ 2

Author(s):

Jun Jiao ◽

Supapan Seraphin

Keyword(s):

Carbon Monoxide ◽

High Temperature ◽

Carbon Content ◽

Arc Discharge ◽

Low Carbon ◽

High Carbon ◽

High Carbon Content ◽

Carbon Nanoclusters ◽

Comparative Manner

The preparation and structural characterization of carbon nanoclusters of different morphologies produced by three different methods and under a variety of conditions is reported. In a comparative manner, the growth phenomena and structural properties of carbon nanoclusters are investigated as synthesized by (a) the high temperature (˜3000 °C) and high carbon-content process of the conventional arc-discharge, (b) the high temperature but low carbon-content process of the modified arc-discharge, and finally (c) the relatively low temperature (˜500 °C) process of Ni catalytic disproportionation of carbon monoxide.

Download Full-text

High-Temperature Mechanical Properties of Al2O3/Ti3SiC2 Multilayer Ceramics

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.280-283.1877 ◽

2007 ◽

Vol 280-283 ◽

pp. 1877-1880 ◽

Cited By ~ 1

Author(s):

Qing Feng Zan ◽

Chang An Wang ◽

Li Min Dong ◽

Yong Huang

Keyword(s):

Mechanical Properties ◽

High Temperature ◽

Room Temperature ◽

Diffusion Creep ◽

Creep Function ◽

High Temperature Mechanical Properties ◽

Multilayer Composites ◽

Dislocation Movement ◽

Monolithic Ceramics ◽

Multilayer Materials

The high-temperature mechanical properties were very important to structural materials, especially structural ceramics. Hence, the strength, elastic modulus, stress relaxation and creep behavior of the multilayer materials at elevated temperature were studied in this paper. According to the curves of mechanical properties varieties with temperature risen from room-temperature to 1300°C, the multilayer materials could remain relatively high mechanical properties until 1150°C. Otherwise, the creep function of the multilayer composites was also determined, in which the stress exponent was 1.4 and activation energy was 204kJ/mol. By contrasting to the monolithic ceramics of Al2O3 and Ti3SiC2, the main creep mechanisms include: interface diffusion creep (in Al2O3 layers), dislocation movement creep, grain delamination and sliding (in Ti3SiC2 layers).

Download Full-text

Effect of Zr Addition on High Temperature Mechanical Properties of Near Alpha Ti-Al-Zr-Sn Based Alloy

Materials Science Forum ◽

10.4028/www.scientific.net/msf.783-786.580 ◽

2014 ◽

Vol 783-786 ◽

pp. 580-583 ◽

Cited By ~ 4

Author(s):

Murugesan Jayaprakash ◽

De Hai Ping ◽

Y. Yamabe-Mitarai

Keyword(s):

Mechanical Properties ◽

High Temperature ◽

Room Temperature ◽

High Temperature Strength ◽

Test Results ◽

High Temperature Mechanical Properties ◽

Ti Alloys ◽

Zr Addition ◽

And Performance ◽

Compressive Tests

Titanium (Ti) alloys are widely used in aerospace industries successfully up to 600°C. Increasing the operating temperature and performance of these alloys would be very useful for fuel economy. Numerous numbers of research works has been focused on the improvement of the high temperature performances of Ti alloys. It has been well known that Zirconium (Zr) is one of the important solid-solution strengthener in Ti-alloys. In the present study, the effect of Zr addition on the microstructure and mechanical properties of the near–α Ti-Al-Zr-Sn based alloys has been investigated.The compression test results showed that Zr addition significantly improves both room temperature and high temperature strength. The results obtained were explained based on the microstructural observation, room temperature and high temperature compressive tests.

Download Full-text

Influence of Al2O3 content on mechanical properties of silica-based ceramic cores prepared by stereolithography

Journal of Advanced Ceramics ◽

10.1007/s40145-021-0513-y ◽

2021 ◽

Author(s):

Wen Zheng ◽

Jia-Min Wu ◽

Shuang Chen ◽

Chang-Shun Wang ◽

Chun-Lei Liu ◽

...

Keyword(s):

Mechanical Properties ◽

High Temperature ◽

Flexural Strength ◽

Room Temperature ◽

Linear Shrinkage ◽

Fused Silica ◽

Al2o3 Content ◽

High Temperature Mechanical Properties ◽

Silica Ceramic ◽

Excellent Chemical

AbstractSilica ceramic cores have played an important part in the manufacture of hollow blades due to their excellent chemical stability and moderate high-temperature mechanical properties. In this study, silica-based ceramics were prepared with Al2O3 addition by stereolithography, and the influence of Al2O3 content on mechanical properties of the silica-based ceramics was investigated. The Al2O3 in silica-based ceramics can improve the mechanical properties by playing a role as a seed for the crystallization of fused silica into cristobalite. As a result, with the increase of Al2O3 content, the linear shrinkage of the silica-based ceramics first decreased and then increased, while the room-temperature flexural strength and the high-temperature flexural strength first increased and then decreased. As the Al2O3 content increased to 1.0 vol%, the linear shrinkage was reduced to 1.64% because of the blocked viscous flow caused by Al2O3. Meanwhile, the room-temperature flexural strength and the high-temperature flexural strength were improved to 20.38 and 21.43 MPa with 1.0 vol% Al2O3, respectively, due to the increased α-cristobalite and β-cristobalite content. Therefore, using the optimal content of Al2O3 in silica-based ceramics can provide excellent mechanical properties, which are suitable for the application of ceramic cores in the manufacturing of hollow blades.

Download Full-text

Performance Analysis of Fire-Resistant H-Beam Steel

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.163-167.2949 ◽

2010 ◽

Vol 163-167 ◽

pp. 2949-2952

Author(s):

Jian Qing Qian ◽

Ji Ping Chen ◽

Bao Qiao Wu ◽

Jie Ca Wu

Keyword(s):

Mechanical Properties ◽

High Temperature ◽

Chemical Composition ◽

Room Temperature ◽

High Temperature Strength ◽

High Temperature Mechanical Properties ◽

H Beam ◽

Hot Rolled ◽

Very High ◽

Room Temperature Strength

The fire-resistant hot-rolled H-beam steel is the newly developed structure material. The development situation of the fire-resistant H-beam steel is briefly introduced. The chemical composition, microstructure, room temperature and high temperature mechanical properties and weldability of several batches of the developed domestic fire-resistant hot-rolled H-beam steels are comprehensively analyzed. The results show that the newly developed hot-rolled fire-resistant H-beam steel has very high room temperature strength, certain high temperature strength, good welding performance, but the toughness needs to be further improved. The performance of web and flange of H-beam steel has large gap.

Download Full-text

Physical and chemical processes in the cavity of the oxygen converter when burning the bath with the afterburning of exhaust gases

Fundamental and applied problems of ferrous metallurgy ◽

10.52150/2522-9117-2019-33-116-128 ◽

2019 ◽

pp. 116-128

Author(s):

A.G. Chernyatevich ◽

L.S. Molchanov ◽

V.V. Vakulchuk ◽

B.Y. Yushkevich

Keyword(s):

High Temperature ◽

Carbon Content ◽

Oxygen Converter ◽

Slag Formation ◽

High Carbon ◽

High Carbon Content ◽

Double Row ◽

Exhaust Gases ◽

Converter Bath ◽

Temperature Modeling

The aim of the study is to study the characteristics of physicochemical processes in the cavity of an oxygen converter when purging a bath through two-tier tuyeres of various designs. The analysis showed that the classical designs of oxygen tuyeres equipped with tips with Laval nozzles do not always satisfy the requirements of the technology. The article presents the results of laboratory high-temperature modeling of the process of purging the converter bath through two-tier tuyeres equipped with tips of various designs. The studies were carried out on a multipurpose installation mounted on the basis of a 150-kg induction furnace and a 60-kg converter manufactured at a scale of 1:18 relative to 160 tons of an industrial unit. It is shown that the use of a two-tier lance provides additional advantages for the smelting process. So, in the initial and main periods of purging the converter bath through a two-tier lance with a double-row tip, it was possible to accelerate the process of slag formation without the addition of fluorspar, to intensify the removal of phosphorus at a high carbon content. Upon completion of the initial purge period at a low metal temperature of 1300-1330 ° C and the corresponding basicity of liquid slag, the degree of dephosphorization of 73.3-79.1% is achieved. When used for blowing two-tier tuyeres with double-row tips, the efficiency of afterburning of CO exhaust gases to CO2 also increases at the same decarburization rate of the bath. Based on the data of high-temperature modeling, the rational design of the two-tier lance has been determined, which ensures: balance of the heat balance; yield increase; creating conditions for the removal of phosphorus at a high carbon content; exclusion of negative effects on the lining.

Download Full-text