共查询到20条相似文献,搜索用时 62 毫秒
1.
采用恒温有限元法,研究了一定温度与氢原子回火脆化对三种不同成分2.25Cr-1Mo钢局部脆断应力的影响,结果发现,可用局部脆断应力σ1的变化衡量材料的回火脆化倾向,但由于晶界上杂质元素与氢原子分布的随机性,可能导致沿晶脆断应力的分析,在降低局部脆断应力的作用下,氢脆与回火脆化具有叠加关系。 相似文献
2.
3.
06MnVL1钢系正火态交货的微珠光体低温(-60℃)用钢,在回火或焊接热循环作用下其母材及焊接热影响区的冲击韧性均有明显下降,严重是影响了此钢的推广和应用。对06MnVA1钢进行了试验、观察和分析,结果表明,这种钢的母材及热影响区经回火或在经受焊接热循环作用后脆化主要是由于超细的V粒子沿位错线的二次析出,以及回火温度和焊接热循环温度峰值达到或超过Acl后空冷时出现岛状相所造成的。 相似文献
4.
5.
6.
7.
8.
9.
X80级管线钢热影响区的局部脆化 总被引:1,自引:0,他引:1
研究了国产X80级管线钢热影响区的冲击韧性和组织的局部脆化.结果表明,该钢的焊接热影响区的冲击韧性较母材降低50%以上;在所研究的20~-40 ℃温度区间内,其断口的宏观形貌特征从部分脆性特征转变为完全的脆性断口;20 ℃放射区断口呈现韧性断裂和解理断裂共存的混合型断口,并且试验温度为20 ℃和0 ℃时,分别在放射区和纤维区可观察到微观裂纹;热影响区断口表层剖面组织为粒状贝氏体,显示出粗晶区的特征.裂纹扩展方向为沿晶界扩展,粒状贝氏体中M/A岛尺寸增大,并存在裂纹穿过岛状物的现象,这是晶界严重脆化的结果. 相似文献
10.
为了探明钢中低熔点元素铋在切削加工和高温变形生产过程中的“两面性”作用,借助切削加工试验、高温热塑性试验及微观组织结构分析,研究了不同温度范围内铋对钢脆化行为的影响。结果表明,在切削加工过程中,低熔点元素铋对钢的脆化作用,使铋易切削钢易于形成对切削加工有利的“C形”脆性屑,从而获得优良的可切削加工性能,该脆化行为主要与钢中铋的液态金属脆化作用有关,显著降低钢在铋熔点温度附近的塑性。在高温变形温度区间,低熔点元素铋对钢脆化行为的影响,主要与奥氏体晶界上铋膜的偏聚有关,脆化晶界,显著降低钢在1 000 ℃及以下试验温度时的热塑性。 相似文献
11.
12.
The Master Curve (MC) approach and the associated reference temperature, T0, as defined in the test standard ASTM E1921, is rapidly moving from the research laboratory to application in integrity assessment of components and structures. T0 is the index temperature for the universal MC, which considers the toughness behaviour of a specific material. “The Structural Integrity Assessment Procedures for European Industry” (SINTAP) contain a MC extension for analysing the fracture behaviour of inhomogeneous ferritic steels. This paper presents the application of the MC approach to the T0 determination of different types of Russian WWER‐type reactor pressure vessel (RPV) steels. In addition the SINTAP‐MC approach was applied to determine an alternative reference temperature, TR. The influence of different microstructures and compositions within one type of RPV steel and the effect of irradiation with fast neutrons on T0 are experimentally evaluated. In general the MC based T0 is about 72 K below the Charpy V‐notch transition temperature related to an impact energy of 48 J. The paper demonstrates the application of MC based T0 and TR as an alternative reference temperature for neutron embrittled RPV steels used in the RPV integrity assessment. 相似文献
13.
14.
15.
超细Ce-Zr-O粉末的制备及其影响因素 总被引:7,自引:1,他引:6
采用共沉淀法在室温下制备超细Ce-Zr-O粉末。通过激光粒度仪(LS-601)、XRD、TG、比表面积测定仪等对合成粉末进行了分析,并考察了料液组成、加料方式、添加剂种类、煅烧温度等合成条件对合成产物粒度的影响。结果表明:采用硝酸铈锆料液为原料、用氨水作沉淀剂、以及加料方式在室温下沉淀,所得沉淀经干燥和煅烧可以得到粒度均匀、悬浮性好的超细Ce-Zr-O粉末。 相似文献
16.
《钢铁研究学报(英文版)》2011,(Z1):412-416
The effect of post weld heat treatment (PWHT) on the toughness of nuclear reactor pressure vessel steel was investigated.Fracture toughness (K JC) and Charpy impact toughness (KVC) were obtained at different temperatures for quenched-tempered (QT) and PWHT A533B steel plates,respectively.The results show that PWHT increases the ductile-brittle transition temperature,and decreases the K JC and KVC.By using SEM and Electron probe micro-analyzer (EPMA),it is found that the size of the precipitation phases increased and molybdenum precipitated during PWHT respectively.The relationship between the size of the precipitation phases and the fracture toughness are analyzed and the influence of microstructure is also briefly discussed. 相似文献
17.
EfectofRareEarthsonTemperedMartensiteEmbritlementofStelGaoGuozhong(高国忠),HeWeiyong(贺维勇),GaoJu(高炬),ChenJizhi(陈继志)(InstituteofM... 相似文献
18.
19.
对一种用于核电站反应堆控制机构的新型不锈钢作了研究。研究结果表明,该不锈钢具有良好的耐晶间腐蚀性能、有较高的抗拉强度和低的屈强比、有良好的抗疲劳性能和断裂韧性。新型不锈钢能满足ASME规范要求和反应堆控制机构的服役要求。 相似文献