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G. D. West - One of the best experts on this subject based on the ideXlab platform.

  • Microstructural Characterization of the Heat-Affected Zones in Grade 92 Steel Welds: Double-Pass and Multipass Welds
    Metallurgical and Materials Transactions A, 2018
    Co-Authors: G. D. West, J. A. Siefert, J. D. Parker, R. C. Thomson
    Abstract:

    The microstructure in the heat-affected zone (HAZ) of multipass welds typical of those used in power plants and made from 9 wt pct chromium Martensitic Grade 92 steel is complex. Therefore, there is a need for systematic microstructural investigations to define the different regions of the microstructure across the HAZ of Grade 92 steel welds manufactured using the traditional arc welding processes in order to understand possible failure mechanisms after long-term service. In this study, the microstructure in the HAZ of an as-fabricated two-pass bead-on-plate weld on a parent metal of Grade 92 steel has been systematically investigated and compared to a complex, multipass thick section weldment using an extensive range of electron and ion-microscopy-based techniques. A dilatometer has been used to apply controlled thermal cycles to simulate the microstructures in distinctly different regions in a multipass HAZ using sequential thermal cycles. A wide range of microstructural properties in the simulated materials were characterized and compared with the experimental observations from the weld HAZ. It has been found that the microstructure in the HAZ can be categorized by a combination of sequential thermal cycles experienced by the different zones within the complex weld metal, using the terminology developed for these regions based on a simpler, single-pass bead-on-plate weld, categorized as complete transformation, partial transformation, and overtempered.

  • Microstructural characterization of the heat-affected zones in Grade 92 steel welds: Double-pass and multipass welds
    2018
    Co-Authors: G. D. West, J. A. Siefert, J. D. Parker, Rachel Thomson
    Abstract:

    The microstructure in the heat affected zone (HAZ) of multipass welds typical of those used in power plant made from 9 wt.% chromium Martensitic Grade 92 steel is complex. There is therefore a need for systematic microstructural investigations to define the different regions of the microstructure across the HAZ of Grade 92 steel welds manufactured using traditional arc welding processes in order to understand possible failure mechanisms after long term service. In this study, the microstructure in the HAZ of an as-fabricated two-pass bead-on-plate weld on a parent metal of Grade 92 steel has been systematically investigated and compared to a complex, multi-pass thick section weldment using an extensive range of electron and ion-microscopy based techniques. A dilatometer has been used to apply controlled thermal cycles to simulate the microstructures in distinctly different regions in a multi-pass HAZ using sequential thermal cycles. A wide range of microstructural properties in the simulated materials were characterised and compared with the experimental observations from the weld HAZ. It has been found that the microstructure in the HAZ can be categorized by a combination of sequential thermal cycles experienced by the different zones within the complex weld metal, using the terminology developed for these regions based on a simpler, single pass bead on plate weld, which have been systematically categorised as Complete Transformation (CT), Partial Transformation (PT) and Over Tempered (OT)

  • The Influence of Thermal Cycles on the Microstructure of Grade 92 Steel
    Metallurgical and Materials Transactions A, 2017
    Co-Authors: G. D. West, J. A. Siefert, J. D. Parker, R. C. Thomson
    Abstract:

    The microstructure in the heat-affected zone (HAZ) of welds made from the 9 wt pct chromium Martensitic Grade 92 steel is complex and has not yet been completely understood. There is a lack of systematic microstructural investigations to define the different regions of the microstructure across the HAZ of Grade 92 steel welds as a function of the welding process. In this study, the microstructure in the HAZ of an as-fabricated single-pass bead-on-plate weld on a parent metal of Grade 92 steel was systematically investigated by using an extensive range of electron and ion-microscopy-based techniques. A dilatometer was used to apply controlled thermal cycles to simulate the microstructures in the different regions of the HAZ. A wide range of microstructural properties in the simulated materials were then characterized and compared with the experimental observations from the weld HAZ. It was found that the microstructure in the HAZ of a single-pass Grade 92 steel weld can be categorized as a function of a decreasing peak temperature reached as (1) the completely transformed (CT) region, in which the original matrix is completely reaustenitized with complete dissolution of the pre-existing secondary precipitate particles; (2) the partially transformed (PT) region, where the original matrix is partially reaustenitized along with a partial dissolution of the secondary precipitate particles from the original matrix; and (3) the overtempered (OT) region, where the pre-existing precipitate particles coarsen. The PT region is considered to be the susceptible area for damage in the commonly reported HAZ failures in weldments constructed from these types of steels.

  • The influence of thermal cycles on the microstructure of Grade 92 steel
    2017
    Co-Authors: G. D. West, J. A. Siefert, J. D. Parker, Rachel Thomson
    Abstract:

    The microstructure in the heat-affected zone (HAZ) of welds made from the 9 wt pct chromium Martensitic Grade 92 steel is complex and has not yet been completely understood. There is a lack of systematic microstructural investigations to define the different regions of the microstructure across the HAZ of Grade 92 steel welds as a function of the welding process. In this study, the microstructure in the HAZ of an as-fabricated single-pass bead-on-plate weld on a parent metal of Grade 92 steel was systematically investigated by using an extensive range of electron and ion-microscopy-based techniques. A dilatometer was used to apply controlled thermal cycles to simulate the microstructures in the different regions of the HAZ. A wide range of microstructural properties in the simulated materials were then characterized and compared with the experimental observations from the weld HAZ. It was found that the microstructure in the HAZ of a single-pass Grade 92 steel weld can be categorized as a function of a decreasing peak temperature reached as (1) the completely transformed (CT) region, in which the original matrix is completely reaustenitized with complete dissolution of the pre-existing secondary precipitate particles; (2) the partially transformed (PT) region, where the original matrix is partially reaustenitized along with a partial dissolution of the secondary precipitate particles from the original matrix; and (3) the overtempered (OT) region, where the pre-xisting precipitate particles coarsen. The PT region is considered to be the susceptible area for damage in the commonly reported HAZ failures in weldments constructed from these types of steels

Rachel Thomson - One of the best experts on this subject based on the ideXlab platform.

  • Microstructural characterization of the heat-affected zones in Grade 92 steel welds: Double-pass and multipass welds
    2018
    Co-Authors: G. D. West, J. A. Siefert, J. D. Parker, Rachel Thomson
    Abstract:

    The microstructure in the heat affected zone (HAZ) of multipass welds typical of those used in power plant made from 9 wt.% chromium Martensitic Grade 92 steel is complex. There is therefore a need for systematic microstructural investigations to define the different regions of the microstructure across the HAZ of Grade 92 steel welds manufactured using traditional arc welding processes in order to understand possible failure mechanisms after long term service. In this study, the microstructure in the HAZ of an as-fabricated two-pass bead-on-plate weld on a parent metal of Grade 92 steel has been systematically investigated and compared to a complex, multi-pass thick section weldment using an extensive range of electron and ion-microscopy based techniques. A dilatometer has been used to apply controlled thermal cycles to simulate the microstructures in distinctly different regions in a multi-pass HAZ using sequential thermal cycles. A wide range of microstructural properties in the simulated materials were characterised and compared with the experimental observations from the weld HAZ. It has been found that the microstructure in the HAZ can be categorized by a combination of sequential thermal cycles experienced by the different zones within the complex weld metal, using the terminology developed for these regions based on a simpler, single pass bead on plate weld, which have been systematically categorised as Complete Transformation (CT), Partial Transformation (PT) and Over Tempered (OT)

  • The influence of thermal cycles on the microstructure of Grade 92 steel
    2017
    Co-Authors: G. D. West, J. A. Siefert, J. D. Parker, Rachel Thomson
    Abstract:

    The microstructure in the heat-affected zone (HAZ) of welds made from the 9 wt pct chromium Martensitic Grade 92 steel is complex and has not yet been completely understood. There is a lack of systematic microstructural investigations to define the different regions of the microstructure across the HAZ of Grade 92 steel welds as a function of the welding process. In this study, the microstructure in the HAZ of an as-fabricated single-pass bead-on-plate weld on a parent metal of Grade 92 steel was systematically investigated by using an extensive range of electron and ion-microscopy-based techniques. A dilatometer was used to apply controlled thermal cycles to simulate the microstructures in the different regions of the HAZ. A wide range of microstructural properties in the simulated materials were then characterized and compared with the experimental observations from the weld HAZ. It was found that the microstructure in the HAZ of a single-pass Grade 92 steel weld can be categorized as a function of a decreasing peak temperature reached as (1) the completely transformed (CT) region, in which the original matrix is completely reaustenitized with complete dissolution of the pre-existing secondary precipitate particles; (2) the partially transformed (PT) region, where the original matrix is partially reaustenitized along with a partial dissolution of the secondary precipitate particles from the original matrix; and (3) the overtempered (OT) region, where the pre-xisting precipitate particles coarsen. The PT region is considered to be the susceptible area for damage in the commonly reported HAZ failures in weldments constructed from these types of steels

R. C. Thomson - One of the best experts on this subject based on the ideXlab platform.

  • Microstructural Characterization of the Heat-Affected Zones in Grade 92 Steel Welds: Double-Pass and Multipass Welds
    Metallurgical and Materials Transactions A, 2018
    Co-Authors: G. D. West, J. A. Siefert, J. D. Parker, R. C. Thomson
    Abstract:

    The microstructure in the heat-affected zone (HAZ) of multipass welds typical of those used in power plants and made from 9 wt pct chromium Martensitic Grade 92 steel is complex. Therefore, there is a need for systematic microstructural investigations to define the different regions of the microstructure across the HAZ of Grade 92 steel welds manufactured using the traditional arc welding processes in order to understand possible failure mechanisms after long-term service. In this study, the microstructure in the HAZ of an as-fabricated two-pass bead-on-plate weld on a parent metal of Grade 92 steel has been systematically investigated and compared to a complex, multipass thick section weldment using an extensive range of electron and ion-microscopy-based techniques. A dilatometer has been used to apply controlled thermal cycles to simulate the microstructures in distinctly different regions in a multipass HAZ using sequential thermal cycles. A wide range of microstructural properties in the simulated materials were characterized and compared with the experimental observations from the weld HAZ. It has been found that the microstructure in the HAZ can be categorized by a combination of sequential thermal cycles experienced by the different zones within the complex weld metal, using the terminology developed for these regions based on a simpler, single-pass bead-on-plate weld, categorized as complete transformation, partial transformation, and overtempered.

  • The Influence of Thermal Cycles on the Microstructure of Grade 92 Steel
    Metallurgical and Materials Transactions A, 2017
    Co-Authors: G. D. West, J. A. Siefert, J. D. Parker, R. C. Thomson
    Abstract:

    The microstructure in the heat-affected zone (HAZ) of welds made from the 9 wt pct chromium Martensitic Grade 92 steel is complex and has not yet been completely understood. There is a lack of systematic microstructural investigations to define the different regions of the microstructure across the HAZ of Grade 92 steel welds as a function of the welding process. In this study, the microstructure in the HAZ of an as-fabricated single-pass bead-on-plate weld on a parent metal of Grade 92 steel was systematically investigated by using an extensive range of electron and ion-microscopy-based techniques. A dilatometer was used to apply controlled thermal cycles to simulate the microstructures in the different regions of the HAZ. A wide range of microstructural properties in the simulated materials were then characterized and compared with the experimental observations from the weld HAZ. It was found that the microstructure in the HAZ of a single-pass Grade 92 steel weld can be categorized as a function of a decreasing peak temperature reached as (1) the completely transformed (CT) region, in which the original matrix is completely reaustenitized with complete dissolution of the pre-existing secondary precipitate particles; (2) the partially transformed (PT) region, where the original matrix is partially reaustenitized along with a partial dissolution of the secondary precipitate particles from the original matrix; and (3) the overtempered (OT) region, where the pre-existing precipitate particles coarsen. The PT region is considered to be the susceptible area for damage in the commonly reported HAZ failures in weldments constructed from these types of steels.

G.b. Kale - One of the best experts on this subject based on the ideXlab platform.

  • Diffusion reaction between Zr-2.5 wt% Nb alloy and Martensitic Grade 403 stainless steel
    Journal of Nuclear Materials, 2001
    Co-Authors: K. Bhanumurthy, R.v. Patil, D Srivatsava, P.s Gawde, G.b. Kale
    Abstract:

    Abstract Diffusion reaction between Zr–2.5 wt% Nb alloy and 403 stainless steel has been investigated by employing miniature type diffusion couples in the temperature range between 750°C and 940°C for 1–240 h. An electron probe microanalyser (EPMA) has been used to establish the concentration penetration profiles across the diffusion zone and a transmission electron microscope (TEM) has been used to identify various phases formed close to the interface. The microstructure of the bonded region on the 403 steel side is essentially a Martensitic structure and remains nearly unchanged during annealing. However, the microstructure of the Zr–2.5 wt% Nb alloy changes substantially, leading to the formation of coarser α phase. The diffusion reaction is extremely sluggish. Localised melting occurs in the specimens annealed at and above 940°C. This is essentially due to the eutectic reaction between zirconium and iron. The experiments confirm that diffusion bonding of 403 steel to Zr–2.5 wt% Nb could be carried out at a pressure of 10 MPa at 900°C for 1 h. The formation of various phases in this multi-phase and multi-component system along with change in their composition with annealing temperature and the nature of reaction products is discussed.

  • diffusion reaction between zr 2 5 wt nb alloy and Martensitic Grade 403 stainless steel
    Journal of Nuclear Materials, 2001
    Co-Authors: K. Bhanumurthy, R.v. Patil, D Srivatsava, P.s Gawde, G.b. Kale
    Abstract:

    Abstract Diffusion reaction between Zr–2.5 wt% Nb alloy and 403 stainless steel has been investigated by employing miniature type diffusion couples in the temperature range between 750°C and 940°C for 1–240 h. An electron probe microanalyser (EPMA) has been used to establish the concentration penetration profiles across the diffusion zone and a transmission electron microscope (TEM) has been used to identify various phases formed close to the interface. The microstructure of the bonded region on the 403 steel side is essentially a Martensitic structure and remains nearly unchanged during annealing. However, the microstructure of the Zr–2.5 wt% Nb alloy changes substantially, leading to the formation of coarser α phase. The diffusion reaction is extremely sluggish. Localised melting occurs in the specimens annealed at and above 940°C. This is essentially due to the eutectic reaction between zirconium and iron. The experiments confirm that diffusion bonding of 403 steel to Zr–2.5 wt% Nb could be carried out at a pressure of 10 MPa at 900°C for 1 h. The formation of various phases in this multi-phase and multi-component system along with change in their composition with annealing temperature and the nature of reaction products is discussed.

J. A. Siefert - One of the best experts on this subject based on the ideXlab platform.

  • Microstructural Characterization of the Heat-Affected Zones in Grade 92 Steel Welds: Double-Pass and Multipass Welds
    Metallurgical and Materials Transactions A, 2018
    Co-Authors: G. D. West, J. A. Siefert, J. D. Parker, R. C. Thomson
    Abstract:

    The microstructure in the heat-affected zone (HAZ) of multipass welds typical of those used in power plants and made from 9 wt pct chromium Martensitic Grade 92 steel is complex. Therefore, there is a need for systematic microstructural investigations to define the different regions of the microstructure across the HAZ of Grade 92 steel welds manufactured using the traditional arc welding processes in order to understand possible failure mechanisms after long-term service. In this study, the microstructure in the HAZ of an as-fabricated two-pass bead-on-plate weld on a parent metal of Grade 92 steel has been systematically investigated and compared to a complex, multipass thick section weldment using an extensive range of electron and ion-microscopy-based techniques. A dilatometer has been used to apply controlled thermal cycles to simulate the microstructures in distinctly different regions in a multipass HAZ using sequential thermal cycles. A wide range of microstructural properties in the simulated materials were characterized and compared with the experimental observations from the weld HAZ. It has been found that the microstructure in the HAZ can be categorized by a combination of sequential thermal cycles experienced by the different zones within the complex weld metal, using the terminology developed for these regions based on a simpler, single-pass bead-on-plate weld, categorized as complete transformation, partial transformation, and overtempered.

  • Microstructural characterization of the heat-affected zones in Grade 92 steel welds: Double-pass and multipass welds
    2018
    Co-Authors: G. D. West, J. A. Siefert, J. D. Parker, Rachel Thomson
    Abstract:

    The microstructure in the heat affected zone (HAZ) of multipass welds typical of those used in power plant made from 9 wt.% chromium Martensitic Grade 92 steel is complex. There is therefore a need for systematic microstructural investigations to define the different regions of the microstructure across the HAZ of Grade 92 steel welds manufactured using traditional arc welding processes in order to understand possible failure mechanisms after long term service. In this study, the microstructure in the HAZ of an as-fabricated two-pass bead-on-plate weld on a parent metal of Grade 92 steel has been systematically investigated and compared to a complex, multi-pass thick section weldment using an extensive range of electron and ion-microscopy based techniques. A dilatometer has been used to apply controlled thermal cycles to simulate the microstructures in distinctly different regions in a multi-pass HAZ using sequential thermal cycles. A wide range of microstructural properties in the simulated materials were characterised and compared with the experimental observations from the weld HAZ. It has been found that the microstructure in the HAZ can be categorized by a combination of sequential thermal cycles experienced by the different zones within the complex weld metal, using the terminology developed for these regions based on a simpler, single pass bead on plate weld, which have been systematically categorised as Complete Transformation (CT), Partial Transformation (PT) and Over Tempered (OT)

  • The Influence of Thermal Cycles on the Microstructure of Grade 92 Steel
    Metallurgical and Materials Transactions A, 2017
    Co-Authors: G. D. West, J. A. Siefert, J. D. Parker, R. C. Thomson
    Abstract:

    The microstructure in the heat-affected zone (HAZ) of welds made from the 9 wt pct chromium Martensitic Grade 92 steel is complex and has not yet been completely understood. There is a lack of systematic microstructural investigations to define the different regions of the microstructure across the HAZ of Grade 92 steel welds as a function of the welding process. In this study, the microstructure in the HAZ of an as-fabricated single-pass bead-on-plate weld on a parent metal of Grade 92 steel was systematically investigated by using an extensive range of electron and ion-microscopy-based techniques. A dilatometer was used to apply controlled thermal cycles to simulate the microstructures in the different regions of the HAZ. A wide range of microstructural properties in the simulated materials were then characterized and compared with the experimental observations from the weld HAZ. It was found that the microstructure in the HAZ of a single-pass Grade 92 steel weld can be categorized as a function of a decreasing peak temperature reached as (1) the completely transformed (CT) region, in which the original matrix is completely reaustenitized with complete dissolution of the pre-existing secondary precipitate particles; (2) the partially transformed (PT) region, where the original matrix is partially reaustenitized along with a partial dissolution of the secondary precipitate particles from the original matrix; and (3) the overtempered (OT) region, where the pre-existing precipitate particles coarsen. The PT region is considered to be the susceptible area for damage in the commonly reported HAZ failures in weldments constructed from these types of steels.

  • The influence of thermal cycles on the microstructure of Grade 92 steel
    2017
    Co-Authors: G. D. West, J. A. Siefert, J. D. Parker, Rachel Thomson
    Abstract:

    The microstructure in the heat-affected zone (HAZ) of welds made from the 9 wt pct chromium Martensitic Grade 92 steel is complex and has not yet been completely understood. There is a lack of systematic microstructural investigations to define the different regions of the microstructure across the HAZ of Grade 92 steel welds as a function of the welding process. In this study, the microstructure in the HAZ of an as-fabricated single-pass bead-on-plate weld on a parent metal of Grade 92 steel was systematically investigated by using an extensive range of electron and ion-microscopy-based techniques. A dilatometer was used to apply controlled thermal cycles to simulate the microstructures in the different regions of the HAZ. A wide range of microstructural properties in the simulated materials were then characterized and compared with the experimental observations from the weld HAZ. It was found that the microstructure in the HAZ of a single-pass Grade 92 steel weld can be categorized as a function of a decreasing peak temperature reached as (1) the completely transformed (CT) region, in which the original matrix is completely reaustenitized with complete dissolution of the pre-existing secondary precipitate particles; (2) the partially transformed (PT) region, where the original matrix is partially reaustenitized along with a partial dissolution of the secondary precipitate particles from the original matrix; and (3) the overtempered (OT) region, where the pre-xisting precipitate particles coarsen. The PT region is considered to be the susceptible area for damage in the commonly reported HAZ failures in weldments constructed from these types of steels