材料期刊网，材料期刊，材料类期刊，材料期刊投稿

氢对Al-Li合金2091-T6组织性能的影响

本文研究了氢含量对Al－Li合金2091－T6薄板力学性能、应力腐蚀开裂寿命（SCCL）、变形机制和断口形貌的影响。结果表明，合金的氢含量由0.92μg／g降低到0.08μg／g时，力学性能和SCCL显著提高．变形机制由切割机制转变为绕过机制，拉伸和应力腐蚀试样的断裂模式由典型的沿晶脆性断裂转变为穿晶韧性断裂，氢脆引起的低韧性沿晶断裂特点完全消失.本文还讨论了脱氢对Al-Li合金变形机制和断裂模式影响的机理，提出了“超低氢Al-Li合金”的概念.

关键词: Al-Li合金2091－T6 , hydrogen embrittlement , mechanical property , stress-corrosion cracking life , deformation mechanism

Fe_3Al与水汽及氧气的表面反应

万晓景 , 朱家红 , 黄胜标

金属学报

用ＡＥＳ及ＳＰＳ研究了Ｆｅ３Ａｌ与水汽及氧气表面反应动力学。表明二者的反应速度都很快，且都在１．５×１０－６Ｐａ·ｓ反应即开始当暴露量达１×１０－４Ｐａ·ｓ，水汽与Ｆｅ３Ａｌ反应达到稳定值，反应产物为Ａｌ２Ｏ３．Ｆｅ３Ａｌ与氧气的反应在１．５×１０－５Ｐａ·ｓ时达到稳定，此时主要是Ａｌ的氧化，当暴露量达３×１０－２Ｐａ·ｓ，Ｆｅ３Ａｌ与氧的反应达到第二阶段平衡，此时主要为Ｆｅ的氧化．上述表面反应动力学可用来圆满解释金属间化合物在不同环境气氛中的拉伸结果．

关键词: Ｆｅ_３Ａｌ , surface reaction , Auger electron spectrum , hydrogen embrittlement

不同时效状态下7050铝合金氢致开裂行为

祁文娟 , 宋仁国 , 祁星 , 金骥戎 , 王超 , 李海

材料热处理学报

采用电化学阴极渗氢、慢应变速率拉伸试验(SSRT)、定氢仪和扫描电子显微镜(SEM)研究了不同时效状态7050铝合金的氢致开裂行为,并应用自由电子理论计算了氢对铝合金晶界上原子结合力的影响.结果表明:氢在铝合金晶界上发生了偏聚,氢的偏聚增大了晶胞点阵常数,降低了晶界原子的平均结合能和原子间的结合力,从而使合金氢脆敏感性(IHE)增加.时效程度对7050铝合金的IHE有很大的影响.在同一充氢条件下,欠时效状态下的铝合金氢含量最大,氢脆效应也最明显,过时效氢含量最低,氢脆效应最弱,峰时效居中.

关键词: 7050铝合金 , 时效 , 氢致开裂 , 氢脆 , 自由电子理论

低驱动电位铝合金牺牲阳极的研制

马力 , 曲本文 , 闫永贵 , 李凯

材料开发与应用

针对传统牺牲阳极由于电位过负导致高强钢氢脆敏感性增加的问题,以Ga为主要活化元素,加入Zn和Si改善阳极的溶解性能,研制了具有良好电化学性能的低驱动电位铝合金牺牲阳极材料,并验证了其对高强钢的保护效果,评价了其对高强钢氢脆敏感性的影响.

关键词: 低驱动电位 , 牺牲阳极 , 电化学性能 , 高强钢 , 氢脆

SURFACE REACTION OF Ni_3Al WITH WATER VAPOR OR OXYGEN

YX. Chen , X.J. Wan and W.X. Xu (Institute of Materials Sciences , Shanghai University , Shanghai 200072 , China)(Shanghai Iron and Steel Research Institute , Shanghai 200940 , China)

金属学报(英文版)

The kinetics of the surface reactions of single crystal Ni3Al and polycrystal line Ni3Al0.00052 wt% B with water vapor or oxygen was investigated using XPS. Both reactions initiate at less than 1.5×10-6 Pa.s exposure. The reaction of Ni3Al does not saturote with water vapor at 0.43 Pa.s; with oxygen at 8.4×10-2 Pa.s and the oxide formed is Al2O3. The kinetics of these reactions can be used to eaplain the different ductility behavior of Ni3Al-based alloys in various environment.

关键词: Ni_3Al , null , null , null

INFLUENCE OF INTERNAL HYDROGEN ON THE HYDROGEN EMBRITTLEMENT OF AUSTENITIC STAINLESS STEEL

Y Tan , D.H Zhouand J. Feng (Institute of Structural Mechanics , Chengdu 610003 , China)

金属学报(英文版)

The HE (hydrogen embrittlement) behavior of two kinds of austenitic stee Cr21Ni6Mn9 and 1Cr18Ni9Ti is reprted in this paper. The factors (temperc-ture/strain rate/stress concentration coefficient and purity of hydrogen) are restricted to the severe conditions under which HE is easy to occur. The concentmtion of in-ternal hydrogen in samples is changed by varying the time during which samples are placed in 24 MPa hydrogen at 473 K Then the tensile properties of the samples are tested. The results indicate that the degree of the hydrogen-induced plastic loss (L)of Cr21Ni6Mn9 is different with the internal hydrogen(CH). Howeven even when CH is as high as 70 PPm L is 15% and the fracture may be explained as a larpe amount of internal hydrogen hinders the cross-slip of dislocations when the steel is deforming.For the metastable steel 1Cr18Ni9Ti the hydrogen-induced plastic loss is severer than that of Cr21Ni6Mn9. When CH is 40 PPm its L is as high as 42%. The mechanism may be explained as a larpe amount of hyderpen decreases the stacking fault enerpy and brittle ε-phase is produed in the high CH areas.

关键词: austenitic stainless steel , null , null , null