Study on Thermal Shock of Sintered Tungsten Alloys for a First Partition of Nuclear Fusion Furnace by the Method of Fracture Mechanics

核聚变炉第一间壁烧结钨合金热冲击断裂力学研究

• 批准号: 05650103
• 负责人: KOBAYASHI Satoshi
• 金额: $ 1.41万
• 依托单位: Nagaoka College of Technology
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (C)
• 财政年份: 1993
• 资助国家: 日本
• 起止时间: 1993 至 1994
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-05650103/
• 关键词: Sintered alloy; High temperature; Strength; Thermal shock; Fractography; Fracture; Tungsten; Notch

Mechanical Properties of W-Ni-Fe sintered alloys with the various volume fractions of tungsten particles were investigated at elevated temperature. 0.2% proof stress and tensile strength of sintered tungste alloys by tension tests, which were higher than those of the other heat-resistance alloy such as 18Cr-8Ni steel, decreased with increasing temperature. Fracture toughness of the sintered tungsten alloys decreased with increasing volume fraction of tungsten particles. When the volume fraction of tungsten particle is low, a stable crack dominantly grows in the Ni-Fe matrix phase, resulting in high toughness. Three point bending tests were carried out in order to study the notch strenght of sintered tungsten alloys. There existed the linear elation between the bending load and the crack lenght. The crack initiation load indicated the low values for the tungsten alloys with high volume fraction of tungsten particle. A crack in the tungsten particle or the tungsten-tungsten grain boundary was observed by the the thermal shock tests for the sintered tungsten alloys. This crack never propagated into the otether tungsten grain or the matrix phase although the thermal shock tests were repeated. The stress distributions around the tungsten particles were analyzed by using a finite element method, and they varied by the change of the volume fraction of tungsten particles. Mechanism of crack initiation in the tungsten particle was investigated by the calculated stress distributions.

研究了钨颗粒体积分数不同的W-Ni-Fe烧结合金的高温力学性能。拉伸试验表明，烧结钨合金的0.2%抗应力和抗拉强度高于18Cr-8Ni钢等其他耐热合金，但随温度升高而降低。随着钨颗粒体积分数的增加，烧结钨合金的断裂韧性降低。当钨颗粒体积分数较低时，稳定裂纹主要生长在Ni-Fe基体相中，韧性较高。为研究烧结钨合金的缺口强度，进行了三点弯曲试验。弯曲荷载与裂纹长度之间存在线性相关性。钨颗粒体积分数高的钨合金的裂纹起裂载荷较小。对烧结钨合金进行热冲击试验，发现钨颗粒或钨-钨晶界出现裂纹。尽管进行了多次热冲击试验，但该裂纹从未扩展到其他钨晶或基体相中。采用有限元方法分析了钨颗粒周围的应力分布，应力分布随钨颗粒体积分数的变化而变化。通过计算得到的应力分布，研究了钨颗粒裂纹的起裂机理。

项目成果

小林訓・武藤睦治・青柳成俊: "タングステン焼結合金の高温強度と破壊形態" 日本機械学会第71期通常総会講演会. (発表予定). (1994)

Ken Kobayashi、Mutsuharu Muto、Shigetoshi Aoyagi：“钨烧结合金的高温强度和断裂形态”在日本机械工程师学会第 71 届普通大会上的演讲（待发表）。

小林訓,武藤睦治他3名: "タングステン焼結合金の強度に及ぼす切欠き半径の影響" 日本機械学会北陸信越支部第32期講演会論文集. 59-60 (1995)

Ken Kobayashi、Mutsuji Muto 等 3 人：“缺口半径对钨烧结合金强度的影响”日本机械工程学会北陆信越分会第 32 届会议记录 59-60（1995 年）。

小林訓・市川国弘・武藤睦治: "タングステン焼結合金の破壊じん性と破壊形態" 日本材料学会誌「材料」. 42. 555-560 (1993)

Ken Kobayashi、Kunihiro Ichikawa、Mutsuharu Muto：“钨烧结合金的断裂韧性和断裂形态”日本材料学会杂志《材料》42. 555-560（1993）。