The Experts below are selected from a list of 34032 Experts worldwide ranked by ideXlab platform
Kaihua Hu - One of the best experts on this subject based on the ideXlab platform.
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microstructure and mechanical properties of high boron white Cast Iron
Materials Science and Engineering A-structural Materials Properties Microstructure and Processing, 2008Co-Authors: Yanxiang Li, Xiang Chen, Kaihua HuAbstract:Abstract In this paper, high boron white Cast Iron, a new kind of wear-resistant white Cast Iron was developed, and its microstructure and mechanical properties were studied. The results indicate that the high boron white Cast Iron comprises a dendritic matrix and an interdendritic eutectic boride in as-Cast condition. The distribution of eutectic boride with a chemical formula of M 2 B (M represents Cr, Fe or Mn) and with a microhardness of HV2010 is much like that of carbide in high chromium white Cast Iron. The matrix includes martensite and a small amount of pearlite. After quenching in air, the matrix changes to martensite, but the morphology of boride remains almost unchanged. In the course of austenitizing, a secondary precipitation with the size of about 1 μm appears, but when tempered at different temperature, another secondary precipitation with the size of several tens of nanometers is found. Both secondary precipitations, which all forms by means of equilibrium segregation of boron, have a chemical formula of M 23 (C,B) 6 . Compared with high chromium white Cast Iron, the hardness of high boron white Cast Iron is almost similar, but the toughness is increased a lot, which attributes to the change of matrix from high carbon martensite in the high chromium white Cast Iron to low carbon martensite in the high boron white Cast Iron. Moreover, the high boron white Cast Iron has a good hardenability.
Yanxiang Li - One of the best experts on this subject based on the ideXlab platform.
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development of boron white Cast Iron
International Journal of Cast Metals Research, 2008Co-Authors: Yanxiang Li, Xiang ChenAbstract:AbstractWith boron substituting for carbon in Cast Iron composition and eutectic borides substituting for eutectic carbides in microstructure as the hard wear resistant phase, a new kind of wear resistant white Cast Iron has been developed. The microstructure and mechanical properties of this new white Cast Iron both in the as Cast state and after appropriate heat treatments were studied. The results show that the as Cast microstructure of the boron white Cast Iron comprises a dendritic matrix and interdendritic eutectics, and the eutectic compound is that of M2B or M′0˙9Cr1˙1B0˙9 type, where M represents Fe, Cr or Mn and M′ represents Fe or Mn. The morphology of the eutectic borides is much like that of carbide in high chromium white Cast Iron, but the hardness of boride is higher than that of carbide. The matrix in as Cast microstructure comprises martensite and pearlite. After austenitising and quenching, the matrix mostly changes to lath type martensite and the eutectic borides remain unchanged. In ad...
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microstructure and mechanical properties of high boron white Cast Iron
Materials Science and Engineering A-structural Materials Properties Microstructure and Processing, 2008Co-Authors: Yanxiang Li, Xiang Chen, Kaihua HuAbstract:Abstract In this paper, high boron white Cast Iron, a new kind of wear-resistant white Cast Iron was developed, and its microstructure and mechanical properties were studied. The results indicate that the high boron white Cast Iron comprises a dendritic matrix and an interdendritic eutectic boride in as-Cast condition. The distribution of eutectic boride with a chemical formula of M 2 B (M represents Cr, Fe or Mn) and with a microhardness of HV2010 is much like that of carbide in high chromium white Cast Iron. The matrix includes martensite and a small amount of pearlite. After quenching in air, the matrix changes to martensite, but the morphology of boride remains almost unchanged. In the course of austenitizing, a secondary precipitation with the size of about 1 μm appears, but when tempered at different temperature, another secondary precipitation with the size of several tens of nanometers is found. Both secondary precipitations, which all forms by means of equilibrium segregation of boron, have a chemical formula of M 23 (C,B) 6 . Compared with high chromium white Cast Iron, the hardness of high boron white Cast Iron is almost similar, but the toughness is increased a lot, which attributes to the change of matrix from high carbon martensite in the high chromium white Cast Iron to low carbon martensite in the high boron white Cast Iron. Moreover, the high boron white Cast Iron has a good hardenability.
S. C. Sharma - One of the best experts on this subject based on the ideXlab platform.
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tensile strength and hardness of sub zero chilled Cast Iron
Materials & Design, 1995Co-Authors: K H W Seah, Joel Hemanth, S. C. SharmaAbstract:Abstract This paper describes the results obtained and the deductions made from a series of ultimate tensile strength (UTS) and hardness tests performed on sub-zero chilled (using liquid nitrogen) Cast Iron containing 1.5% Cu, and of chromium contents ranging from 0.0% to 0.2%. By using copper chills of different thicknesses, the effect on UTS and hardness of varying the chill rate was also examined. All the tests were carried out in conformance with AFS (American Foundryman's Society) standards. It was found that both the UTS and hardness are significantly increased when chromium content and/or rate of cooling are increased. Moreover, it was found that, like steel and grey Cast Iron, the hardness of sub-zero chilled Cast Iron has a definite linear relationship with the UTS. This means that it is possible to predict the hardness if the UTS is known and vice versa.
Jayantha Kodikara - One of the best experts on this subject based on the ideXlab platform.
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classification of major cohorts of australian pressurised Cast Iron water mains for pipe renewal
Australian journal of water resources, 2017Co-Authors: Rui Jiang, Suranji Rathnayaka, Benjamin Shannon, Christopher Hutchinson, Xiao Ling Zhao, Jayantha KodikaraAbstract:AbstractCast Iron pipes buried between the 1860s and 1980s still account for a significant proportion of the Australian water transmission network, and failure rates of Cast Iron trunk mains have risen in the past decades. In Australian cities, the manufacturing methods and corrosion mitigation techniques used in Cast Iron pipes are strongly correlated with the pipeline burial year. This paper introduces an approach to summarise the remaining in service Cast Iron trunk mains into several cohorts, in order to identify the critical pipelines with high potential of longitudinal fracture in pipe barrels. Despite the various manufacturers and Casting moulds used in Australian Cast Iron pipes, two major cohorts, static and spun Cast Iron pipes, were identified based on manufacturing methods, material properties, microstructural analysis and wall thicknesses. A statistical analysis confirmed that spun Cast pipes have higher burst rates and relatively short life spans than statically Cast pipes, evidently due to ...
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Experimental evaluation of bursting capacity of corroded grey Cast Iron water pipeline
Structure and Infrastructure Engineering, 2017Co-Authors: Suranji Rathnayaka, Benjamin Shannon, Dilan Robert, Jayantha KodikaraAbstract:AbstractCast Iron was used in the water industry prior to 1970 and a large number of Cast Iron pipes still remain as trunk mains. These pipes have been subjected to different levels of corrosion and variety of loading conditions. This leads Cast Iron pipes to fail in the field without prior warning. Water utilities are seeking solutions to optimise Cast Iron pipe renewal and rehabilitation programs for critical water mains (diameter ≥ 300 mm). A new experimental set-up has been developed at Monash University in order to perform burst testing of large diameter Cast Iron pipes (diameter ≥ 300 mm). A section of Cast Iron pipe, extracted during maintenance in Sydney, was laser scanned to determine the remaining thickness of the pipe (minimum of 7–8 mm at the most critical patches). Although the pipe was pressurised to 3.6 MPa, catastrophic failure did not occur. Water leakage from the two critically corroded patches was observed at around 3.25–3.45 MPa internal pressure. Strain results on the outer pipe surfa...
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probabilistic physical modelling of corroded Cast Iron pipes for lifetime prediction
Structural Safety, 2017Co-Authors: Dilan Robert, Chunshun Zhang, David Zhang, Jayantha KodikaraAbstract:Cast Iron was the dominant material for buried pipes for water networks prior to the 1970s in Australia and overseas. At present, many water utilities still have a significant amount of ageing Cast Iron pipes. Cast Iron is a brittle material and when large diameter Cast Iron pipes (diameters above 300 mm) further deteriorate, the consequences of failure can be substantial. Focusing on the likelihood of failure to assist risk assessment, this paper examines the performance of large-diameter Cast Iron pipes using probabilistic analysis, incorporating uncertainties of governing variables. Finite element analysis is first conducted to study the physical mechanism of buried pipes subjected to complex envIronmental conditions. The deterioration of Cast Iron pipes due to corrosion is considered on the basis of recent research. The uncertainties of governing variables, such as the physical properties of soil, Cast Iron, water pressure and corrosion patterns, in pipe failure risk assessment are considered. Using probabilistic physical modelling, the lifetime probability of failure is derived and a time-dependent sensitivity analysis is presented. The results of this probabilistic physical modelling are compared with cohorts of failure data from two Australian water utilities to examine the underlying trends from both physical modelling and statistical analysis.
Xiang Chen - One of the best experts on this subject based on the ideXlab platform.
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development of boron white Cast Iron
International Journal of Cast Metals Research, 2008Co-Authors: Yanxiang Li, Xiang ChenAbstract:AbstractWith boron substituting for carbon in Cast Iron composition and eutectic borides substituting for eutectic carbides in microstructure as the hard wear resistant phase, a new kind of wear resistant white Cast Iron has been developed. The microstructure and mechanical properties of this new white Cast Iron both in the as Cast state and after appropriate heat treatments were studied. The results show that the as Cast microstructure of the boron white Cast Iron comprises a dendritic matrix and interdendritic eutectics, and the eutectic compound is that of M2B or M′0˙9Cr1˙1B0˙9 type, where M represents Fe, Cr or Mn and M′ represents Fe or Mn. The morphology of the eutectic borides is much like that of carbide in high chromium white Cast Iron, but the hardness of boride is higher than that of carbide. The matrix in as Cast microstructure comprises martensite and pearlite. After austenitising and quenching, the matrix mostly changes to lath type martensite and the eutectic borides remain unchanged. In ad...
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microstructure and mechanical properties of high boron white Cast Iron
Materials Science and Engineering A-structural Materials Properties Microstructure and Processing, 2008Co-Authors: Yanxiang Li, Xiang Chen, Kaihua HuAbstract:Abstract In this paper, high boron white Cast Iron, a new kind of wear-resistant white Cast Iron was developed, and its microstructure and mechanical properties were studied. The results indicate that the high boron white Cast Iron comprises a dendritic matrix and an interdendritic eutectic boride in as-Cast condition. The distribution of eutectic boride with a chemical formula of M 2 B (M represents Cr, Fe or Mn) and with a microhardness of HV2010 is much like that of carbide in high chromium white Cast Iron. The matrix includes martensite and a small amount of pearlite. After quenching in air, the matrix changes to martensite, but the morphology of boride remains almost unchanged. In the course of austenitizing, a secondary precipitation with the size of about 1 μm appears, but when tempered at different temperature, another secondary precipitation with the size of several tens of nanometers is found. Both secondary precipitations, which all forms by means of equilibrium segregation of boron, have a chemical formula of M 23 (C,B) 6 . Compared with high chromium white Cast Iron, the hardness of high boron white Cast Iron is almost similar, but the toughness is increased a lot, which attributes to the change of matrix from high carbon martensite in the high chromium white Cast Iron to low carbon martensite in the high boron white Cast Iron. Moreover, the high boron white Cast Iron has a good hardenability.
