材料期刊网

几种阴离子对316L不锈钢亚稳态孔蚀行为的影响

王海涛 , 赵景茂 , 左禹

中国腐蚀与防护学报

用恒电位和动电位极化法研究了PO3-4、CrO2- 4、SO2-4和NO-3 4种阴离子对316L不锈钢亚稳态孔蚀行为的影响.4种阴 离子均抑制亚稳态小孔的形核速率和生长速率，其中PO3-4离子作用最强，CrO 2-4离子次之，SO2-4和NO-3离子作用较弱.亚稳态孔蚀开始出现的电位 Em和稳定孔蚀电位Ep均随离子浓度的对数增大而直线升高.讨论了不同离子的作 用机制.

关键词: 亚稳态孔蚀 , anion , nucleation , propagation

Possibility of (11(1)over-bar)(TB) accommodation mechanism for type-I twin intersection in gamma-TiAl during room-temperature deformation

Philosophical Magazine Letters

Three intersection mechanisms with the gliding planes (11(1) over bar)(TB), (001)(TB) and (11(5) over bar)(TB) respectively have been observed by high-resolution electron microscopy in, the type-I twin intersection of gamma -TiAl. It was found that the intersection mechanism that occurred was related to the thickness of the incident twin. The accommodation mechanism on the (11(1) over bar)(TB) atomic;plane is preferred when the incident twin becomes very thin. The dislocation dissociations of the (11(1) over bar)(TB) plane accommodation are the most energetically unfavourable of the dissociations of the three intersection mechanisms; however, the resultant dislocations on the (11(1) over bar)(TB) planes are the easiest to propagate away from the intersection area. Accordingly, (11(1) over bar)(TB) atomic plane accommodation is considered to be the only mechanism allowing shear transmission under the small local stress of the pile-up of the incident twinning partials.

关键词: propagation

METHOD FOR CALCULATION AND SIMULATION ON PROPAGATION OF SURFACE CRACK ON SPHERICAL VESSELS MADE OF STEELS

T.J.Bai 1 , 2) and C.F.Ren 1) 1) Shenyang University , Shenyang 110044 , China 2) Institute of Metal Research , The Chinese Academy of Sciences , Shenyang 110015 , China

金属学报(英文版)

To avoid leaking or bursing by crack on surface of preddure vessels made of streels,a method for analyzing the principle of propagation of a surface crack is established,and used on a spherical vessel with program calculation and simulation,the program is written in QBASIC and the reaults are provided and discussed.

关键词: spherical vessel , null , null , null

2524-T34合金疲劳裂纹的萌生和扩展行为

郑子樵 , 陈圆圆 , 钟利萍 , 佘玲娟 , 翟同广

中国有色金属学报

通过四点弯曲疲劳试验研究2524-T34板材的疲劳性能,借助金相和扫描电镜观察疲劳裂纹的萌生和扩展行为.结果表明:2524合金具有良好的疲劳性能,疲劳强度达到屈服强度的80%以上;疲劳裂纹主要在第二相粒子以及第二相粒子/基体界面萌生,裂纹扩展过程中的偏转与晶界的阻碍有关;相邻晶粒内两个有利滑移面之间的位向差是控制裂纹通过晶界扩展的重要因素.

关键词: 2524合金 , 疲劳裂纹 , 萌生 , 扩展 , 显微组织

03Cr16Mn14Mo2N奥氏体不锈钢的热疲劳行为

徐桂芳 , 严羽 , 徐文慧 , 程晓农 , 李冬升

机械工程材料 doi:10.11973/jxgccl201612022

对新型高氮低镍03Cr16Mn14Mo2N奥氏体不锈钢进行了不同上限温度下的热疲劳试验，通过光学显微镜观察了热疲劳裂纹的萌生及扩展，研究了其热疲劳行为.结果表明：热疲劳裂纹的孕育期随上限温度的升高而缩短，其扩展速率随着循环次数的增加呈先增大后减小的变化趋势；随着上限温度的升高，试验钢V型缺口处的裂纹扩展至0．5 mm时所需的热疲劳循环次数显著降低；热疲劳裂纹在 V 型缺口处优先萌生，随着热循环次数的增加，晶界和孪晶界也成为裂纹源，裂纹主要沿晶界扩展.

关键词: 03Cr16Mn14Mo2N钢 , 热疲劳裂纹 , 萌生 , 扩展

蒸汽射流压力振荡传播特性实验研究

邱斌斌 , 刘继平 , 赵伟月 , 赵全斌 , 陈伟雄 , 种道彤 , 严俊杰 , 武心壮

工程热物理学报

对蒸汽质量流率298 kg/(m2.s),水温20～70℃的蒸汽射流凝结压力振荡的传播特性进行了实验研究.发现不同无量纲轴向距离处的压力振荡波峰波谷基本吻合,随无量纲轴向距离的增加压力振荡频率不变,振荡强度衰减,且没有出现反射叠加现象.压力振荡幅值随无量纲轴向距离的增加而减小,随冷却水温的升高先增大后减小.根据实验结果拟合得到了不同工况和空间位置压力振荡幅值的实验关联式,预测误差在-30％～20％以内.

关键词: 蒸汽射流 , 压力振荡 , 传播