TAN YiDalian University of Technology
,
Dalian
,
ChinaSHINODA THitachi Research Laboratory
,
Hitachi Ltd. 391-12 Hitachi
,
JapanMISHIMA YTokyo Institute of Technology
,
Nagatuta. Midori-Ku
,
Yokohama 227
,
JapanSUZUKI TDepartment of Metallurgical Engineering
,
Tokyo Institute of Technology. Ookayama
,
Meguro-Ku
,
Tokyo 152
,
Japan
金属学报(英文版)
The effects of boron addition on defect hardening at room temperature and on high temperature creep properties are investigated in the B2 NiAl intermetallic compound. It is found that boron addition is effective on increasing the room temperature hardeness on the Ni-rich side but it has no effect on the A1-rich side of stoichiometry. These observations are attributed to interstitial dissolution of boron in Ni-rich NiAl and to a lack of solubility and also due to an enrichment at grain boundaries on the A1-rich side. The similar effect is found in high temperature creep resistance of NiAl by boron addition. The high temperature creep resistance increases on the Ni-rich side but it does not affect the A1-rich side of off-stoiciometry.
关键词:
孙静亚
,
王惠君
稀有金属
doi:10.3969/j.issn.0258-7076.2006.01.015
对D152树脂吸附镝(Ⅲ)的过程及镝在D152树脂上的吸附行为进行了研究. 研究了介质pH、温度、吸附时间、 树脂量等因素对吸附过程的影响. 实验结果表明: D152树脂对镝(Ⅲ)的吸附在pH=5.93的Hac-NaAc的缓冲溶液中为最佳. 25 ℃时静态饱和吸附量为314.6 mg·g-1(干树脂). 用1.0 mol·L-1的HCl溶液作为解吸剂, 解吸率为96.2%;D152树脂对镝(Ⅲ)的表观吸附活化能Ea=18.28 kJ·mol-1, 表观吸附速率常数k298=2.54×10-5 s-1, k308=2.93×10-5 s-1, k318=4.05×10-5 s-1, 测得热力学参数分别为ΔH=18.19 kJ·mol-1, ΔG=-0.88 kJ·mol-1, ΔS=63.99 J·mol-1·K-1, 等温吸附服从Freundlich经验式. 并用化学和红外光谱的方法探求树脂对镝(Ⅲ)的吸附机制.
关键词:
D152树脂
,
吸附
,
机制
,
镝(Ⅲ)
YANG Gang
,
et al
钢铁研究学报(英文版)
The brittleness of M152 martensitic heat resistant steel due to slow cooling during quenching was experimentally investigated by means of mechanical property test, TEM and XRD analysis. The results showed that the nonreversal brittleness of M152 steel due to slow cooling during quenching was caused by the continuous precipitation of M23C6 along prior austenite grain boundaries and of M2C along prior residual austenite film. The residual austenite in the steel was unstable and may decompose due to the precipitation of second phase during the process of slow cooling after quenching. The low cooling rate in the temperature range from 820 to 660℃ has a strong effect on the impact toughness of the steel, the precipitation of second phase in the same temperature range results in nonreversal brittle.
关键词:
M152 martensitic steel;brittleness;M2C carbides;decomposition of residual austenite
杨钢
,
郭永华
,
刘新权
,
马风春
,
宋玺玉
,
张秀丽
钢铁
采用力学性能测试、金相分析及TEM微观结构分析,研究了M152马氏体耐热钢在595℃长期时效过程中的力学性能和结构变化,并探讨了时效脆化机制.结果表明:在595℃时效过程中,发生了显著的回复.位错密度下降,且原始组织中弥散分布的M2C和M7C3碳化物逐渐转变成M23C6碳化物,并聚集长大,导致强度逐渐降低;时效脆化的主要原因是杂质元素的非平衡晶界偏聚和碳化物的晶界析出共同作用,时效初期的脆化主要是由于MzC碳化物沿马氏体板条界的连续析出造成的.
关键词:
M152马氏体耐热钢
,
力学性能
,
时效
,
脆化机制
杨钢 刘新权 杨沐鑫 马风春 宋玺玉 张秀丽
钢铁
采用力学性能测试、金相分析以及TEM微观结构分析，研究了M152马氏体耐热钢在595℃长期时效过程中的力学性能和结构变化，并探讨了时效脆化机制，结果表明：在595℃时效过程中，发生了显著的回复，位错密度下降，且原始组织中弥散分布的M2C和M7C3碳化物逐渐转变成M23C6型碳化物，并聚集长大，导致强度逐渐降低；时效脆化的主要原因是杂质元素的非平衡晶界偏聚和碳化物的晶界析出共同作用，时效初期的脆化主要是由于M2C型碳化物沿马氏体板条界的连续析出造成的。
关键词:
M152马氏体耐热钢;力学性能;时效;脆化机制
