The Experts below are selected from a list of 0 Experts worldwide ranked by ideXlab platform
Hirosada Irie - One of the best experts on this subject based on the ideXlab platform.
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Effects of Full Annealing Heat Treatment on Long-term Creep Strength of 2.25Cr-1Mo Steel Welded Joint
Quarterly Journal of The Japan Welding Society, 2003Co-Authors: Kazuhiro Kimura, Takashi Watanabe, Hiromichi Hongo, Masayoshi Yamazaki, Junichi Kinugawa, Hirosada IrieAbstract:Long-term creep strength of Cr-Mo steel with Fully annealed ferrite and pearlite microstructure is higher than those of the steels with martensite, tempered martensite and bainite microstructures. In this study, influence of post weld heat treatment at the temperature of austenite single phase region(Full Annealing PWHT) on long-term creep strength at 550°C has been investigated on 2.25Cr-1Mo steel, in comparison with that of normal post weld heat treatment at the temperature below A C1 (standard PWHT). Creep rupture strength of the welded joint subjected to standard PWHT is lower than those of base metal and weld metal in the short-term. However, such differences in creep rupture strength disappear after long-term creep exposure for about 50,000h at 550°C. On the other hand, creep strength of the welded joint subjected to Full Annealing PWHT is obviously higher than those of the welded joint subjected to standard PWHT, base metal and weld metal in the long-term condition. It may be also expected to reduce a probability of mechanical damage such as Type IV cracking by the Full Annealing PWHT, since inhomogeneous microstructures in weld metal and heat affected zone have been essentially extinguished. Full Annealing at the temperature of austenite single phase region has been proposed as a new post weld heat treatment condition available to obtain high creep strength and to improve a reliability of welded joint for low alloy Cr-Mo steels.
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Effect of Full Annealing PWHT on a Long -term Creep Strength of 2.25Cr-1Mo Steel Welded Joint
2003Co-Authors: Kazuhiro Kimura, Takashi Watanabe, Hiromichi Hongo, Masayoshi Yamazaki, Junichi Kinugawa, Hirosada IrieAbstract:The effect of a Full Annealing post weld heat treatment, in the austenitic single phase temperature region, on the long-term creep strength of 2.25Cr -1Mo steel has been investigated and compared with that of a normal PWHT, at a temperature below AC1. The creep rupture strength of the welded joint subjected to a normal PWHT is lower , in the short-term, than those of the base metal and weld metal. These differences in creep strength disappear after long-term exposure for about 50,000h at 550 o C. On the other hand, the creep strength of the welded joint subjected to a Full Annealing PWHT is higher than those of the other steels in the long-term condition. The Full Annealing PWHT is also expected to reduce the probability of type IV cracking.. Full Annealing in the austenite single phase temperature region has been proposed as a new PWHT condition to attain high creep strength and to improve the reliability of welded joints.
Noriaki Okamoto - One of the best experts on this subject based on the ideXlab platform.
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Crystallization‐induced stress in phosphorus‐doped amorphous silicon thin films
Journal of Applied Physics, 1994Co-Authors: Hideo Miura, Noriaki OkamotoAbstract:The effect of phosphorus doping on the crystallization‐induced stress of silicon thin films is investigated experimentally using a scanning laser microscope. Though the intrinsic stress of the phosphorus‐doped amorphous silicon films and the crystallization‐induced stress of the films do not change, regardless of the doped phosphorus concentration, the final residual stress of the film after Full Annealing depends on the phosphorus concentration. The final stress decreases by increasing the dopant concentration. In addition, phosphorus doping lowers the crystallization temperature of the amorphous silicon thin films. The existing phosphorus at the interface of the film and the base oxide film is found to change the crystallization mechanism and the magnitude of the stress developed.
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CRYSTALLIZATION-INDUCED STRESS IN PHOSPHORUS-DOPED AMORPHOUS SILICON THIN FILMS
Journal of Applied Physics, 1994Co-Authors: Hideo Miura, Noriaki OkamotoAbstract:The effect of phosphorus doping on the crystallization‐induced stress of silicon thin films is investigated experimentally using a scanning laser microscope. Though the intrinsic stress of the phosphorus‐doped amorphous silicon films and the crystallization‐induced stress of the films do not change, regardless of the doped phosphorus concentration, the final residual stress of the film after Full Annealing depends on the phosphorus concentration. The final stress decreases by increasing the dopant concentration. In addition, phosphorus doping lowers the crystallization temperature of the amorphous silicon thin films. The existing phosphorus at the interface of the film and the base oxide film is found to change the crystallization mechanism and the magnitude of the stress developed.
Kazuhiro Kimura - One of the best experts on this subject based on the ideXlab platform.
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Effects of Full Annealing Heat Treatment on Long-term Creep Strength of 2.25Cr-1Mo Steel Welded Joint
Quarterly Journal of The Japan Welding Society, 2003Co-Authors: Kazuhiro Kimura, Takashi Watanabe, Hiromichi Hongo, Masayoshi Yamazaki, Junichi Kinugawa, Hirosada IrieAbstract:Long-term creep strength of Cr-Mo steel with Fully annealed ferrite and pearlite microstructure is higher than those of the steels with martensite, tempered martensite and bainite microstructures. In this study, influence of post weld heat treatment at the temperature of austenite single phase region(Full Annealing PWHT) on long-term creep strength at 550°C has been investigated on 2.25Cr-1Mo steel, in comparison with that of normal post weld heat treatment at the temperature below A C1 (standard PWHT). Creep rupture strength of the welded joint subjected to standard PWHT is lower than those of base metal and weld metal in the short-term. However, such differences in creep rupture strength disappear after long-term creep exposure for about 50,000h at 550°C. On the other hand, creep strength of the welded joint subjected to Full Annealing PWHT is obviously higher than those of the welded joint subjected to standard PWHT, base metal and weld metal in the long-term condition. It may be also expected to reduce a probability of mechanical damage such as Type IV cracking by the Full Annealing PWHT, since inhomogeneous microstructures in weld metal and heat affected zone have been essentially extinguished. Full Annealing at the temperature of austenite single phase region has been proposed as a new post weld heat treatment condition available to obtain high creep strength and to improve a reliability of welded joint for low alloy Cr-Mo steels.
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Effect of Full Annealing PWHT on a Long -term Creep Strength of 2.25Cr-1Mo Steel Welded Joint
2003Co-Authors: Kazuhiro Kimura, Takashi Watanabe, Hiromichi Hongo, Masayoshi Yamazaki, Junichi Kinugawa, Hirosada IrieAbstract:The effect of a Full Annealing post weld heat treatment, in the austenitic single phase temperature region, on the long-term creep strength of 2.25Cr -1Mo steel has been investigated and compared with that of a normal PWHT, at a temperature below AC1. The creep rupture strength of the welded joint subjected to a normal PWHT is lower , in the short-term, than those of the base metal and weld metal. These differences in creep strength disappear after long-term exposure for about 50,000h at 550 o C. On the other hand, the creep strength of the welded joint subjected to a Full Annealing PWHT is higher than those of the other steels in the long-term condition. The Full Annealing PWHT is also expected to reduce the probability of type IV cracking.. Full Annealing in the austenite single phase temperature region has been proposed as a new PWHT condition to attain high creep strength and to improve the reliability of welded joints.
Hideo Miura - One of the best experts on this subject based on the ideXlab platform.
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Crystallization‐induced stress in phosphorus‐doped amorphous silicon thin films
Journal of Applied Physics, 1994Co-Authors: Hideo Miura, Noriaki OkamotoAbstract:The effect of phosphorus doping on the crystallization‐induced stress of silicon thin films is investigated experimentally using a scanning laser microscope. Though the intrinsic stress of the phosphorus‐doped amorphous silicon films and the crystallization‐induced stress of the films do not change, regardless of the doped phosphorus concentration, the final residual stress of the film after Full Annealing depends on the phosphorus concentration. The final stress decreases by increasing the dopant concentration. In addition, phosphorus doping lowers the crystallization temperature of the amorphous silicon thin films. The existing phosphorus at the interface of the film and the base oxide film is found to change the crystallization mechanism and the magnitude of the stress developed.
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CRYSTALLIZATION-INDUCED STRESS IN PHOSPHORUS-DOPED AMORPHOUS SILICON THIN FILMS
Journal of Applied Physics, 1994Co-Authors: Hideo Miura, Noriaki OkamotoAbstract:The effect of phosphorus doping on the crystallization‐induced stress of silicon thin films is investigated experimentally using a scanning laser microscope. Though the intrinsic stress of the phosphorus‐doped amorphous silicon films and the crystallization‐induced stress of the films do not change, regardless of the doped phosphorus concentration, the final residual stress of the film after Full Annealing depends on the phosphorus concentration. The final stress decreases by increasing the dopant concentration. In addition, phosphorus doping lowers the crystallization temperature of the amorphous silicon thin films. The existing phosphorus at the interface of the film and the base oxide film is found to change the crystallization mechanism and the magnitude of the stress developed.
Na-ra Park - One of the best experts on this subject based on the ideXlab platform.
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Erratum to: Wear characteristics of Stellite6 and NOREM02 hardfaced SKD61 hot working tool steel at the elevated temperature
International Journal of Precision Engineering and Manufacturing, 2014Co-Authors: Na-ra Park, Dong-gyu AhnAbstract:Recently, interest in hardfacing technology has steadily increased in effort to improve wear characteristics of hot forming dies. The objective of this paper is to investigate wear characteristics of Stellite6 and NOREM02 hardfaced SKD61 hot working tools steel at the elevated temperature. Stellite6 and NOREM02 superalloys are deposited onto the SKD61 hot working tool steel using the laser-aided direct metal rapid tooling (DMT) process. In order to examine the influence of the hardfacing materials on the hardness of hardfaced specimens, hardness experiments are performed beyond the Full Annealing temperature of the SKD61 material. Pin-on-disk experiments are carried out to examine wear characteristics, including the worn volume, the worn depth, the worn width, and the friction induced work hardening, of the hardfaced specimens at the elevated temperature. The morphology in the vicinity of the worn region is observed by a digital microscope and a scanning electronic microscope (SEM) to investigate the formation and the microstructure of the worn region. In addition, the efficiency of the hardfaced specimen is discussed via the comparison of wear characteristics of superalloy hardfaced specimens with those of the SKD61 specimen.
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Wear characteristics of Stellite6 and NOREM02 hardfaced SKD61 hot working tool steel at the elevated temperature
International Journal of Precision Engineering and Manufacturing, 2014Co-Authors: Na-ra Park, Dong-gyu AhnAbstract:Recently, interest in hardfacing technology has steadily increased in effort to improve wear characteristics of hot forming dies. The objective of this paper is to investigate wear characteristics of Stellite6 and NOREM02 hardfaced SKD61 hot working tools steel at the elevated temperature. Stellite6 and NOREM02 superalloys are deposited onto the SKD61 hot working tool steel using the laser-aided direct metal rapid tooling (DMT) process. In order to examine the influence of the hardfacing materials on the hardness of hardfaced specimens, hardness experiments are performed beyond the Full Annealing temperature of the SKD61 material. Pin-on-disk experiments are carried out to examine wear characteristics, including the worn volume, the worn depth, the worn width, and the friction induced work hardening, of the hardfaced specimens at the elevated temperature. The morphology in the vicinity of the worn region is observed by a digital microscope and a scanning electronic microscope (SEM) to investigate the formation and the microstructure of the worn region. In addition, the efficiency of the hardfaced specimen is discussed via the comparison of wear characteristics of superalloy hardfaced specimens with those of the SKD61 specimen.
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A study on the effects of hardfacing thickness on wear characteristics of Stellite21 hardfaced STD61 hotworking tool steel at the elevated temperature
International Journal of Precision Engineering and Manufacturing, 2014Co-Authors: Na-ra ParkAbstract:The aim of this paper is to investigate the effects of hardfacing thickness on wear characteristics of Stellite21 hardfaced STD 61 hotworking tool steel at the elevated temperature. Stellite21 super-alloy is deposited on the STD61 hot-working tool steel to fabricate the specimen using a laser-aided direct metal rapid tooling process. Several pin-on-disk wear experiments are carried out at temperatures beyond the Full Annealing temperature of the STD61. The hardness, the friction induced work hardening, the weight loss, the wear depth, and the wear width of each specimen are measured to quantitatively investigate the influence of the hardfacing thickness on the wear characteristics. The variation of friction characteristics of the worn region according to the hardfacing thickness is examined via the measurement of friction coefficients and the observation of morphologies of the worn regions for different specimens. From the results of these investigations, the proper thickness of the Stellite21 hardfaced layer on STD61 hot-working tool steel is estimated.
