Development of prediction model for high temperature damage and fracture of advanced heat resisting materials under multiaxial stress condition.

2016 Fiscal Year Final Research Report

• Project/Area Number: 26420036
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Materials/Mechanics of materials
• Research Institution: National Institute for Materials Science
• Principal Investigator: TABUCHI MASAAKI 国立研究開発法人物質・材料研究機構, 構造材料研究拠点, グループリーダー (60354239)
• Project Period (FY): 2014-04-01 – 2017-03-31
• Keywords: 耐熱材料 / USCプラント / クリープ / 溶接継手 / 損傷評価

Outline of Final Research Achievements

In order to decrease CO2 emission, researches to increase temperature and pressure of steam by using high strengthened material in the thermal power plant. In the present research, long-term creep rupture data from 30000h to 70000h of high Cr steel welds used in USC plant were obtained. It was clarified that creep damages initiate not only in HAZ but also in weld metal. It was found that the hardness of the weld metal decreased rapidly after about 10000 h creep at 600C due to the recovery of microstructures. Small number density of precipitates promote the recovery of the weld metal. Computational system to predict fracture life of welded component was developed and improved. A method that can predict experimental results well was proposed. Creep and crack growth tests were also conducted for advanced steel and weld that are used next generation A-USC power plant. Mechanisms and properties of strength and fracture of advanced high-B 9Cr steel and dissimilar weld joint were clarified.

Free Research Field

材料強度