郭建亭
,
孙超
,
李辉
,
管恒荣
金属学报
本文研究了含硼量为0-2.22at.-％的Ni_3Al在750-1150℃和3-100h条件下的氧化行为。结果表明,不同硼含量的Ni_3Al合金在不同温度下的氧化动力学曲线基本都符合抛物线规律。硼含量在0.52-1.37at。-％时抗氧化性能最好。研究了氧化膜的形态与结构。0-1.37at.-％B的Ni_3Al合金,表面形成以Al_2O_3为主的氧化膜,并含有少量NiO和NiAl_2O_4,含有2.22at.-％B的Ni_3Al合金,表面生成复杂的硼氧化物,破坏Al_2O_3膜的完整性,抗氧化性最差。但无硼合金中,NiAl_2O_4的含量最高,并在试样冷却过程中几乎全部剥离。
关键词:
金属间化合物
,
Ni_3Al_2
,
oxidation
,
boron
沈显璞
,
王继业
,
杨德庄
,
R.PRIESTNER
金属学报
本文研究了硼对低碳低合金钢经(α+γ)区加热形成的奥氏体的淬透性的影响。结果表明,增加硼含量(从0.0005到0.0029％),将减少亚温区加热时形成的奥氏体含量。但明显增加了奥氏体的淬透性,并且降低了马氏体含量及钢的拉伸性能对冷却速度变化的敏感性。同位素示踪分析表明,在亚温区加热时,硼原子仍明显分布在原正火态奥氏体晶界上,没有见到硼原子向α/γ相界的迁移和偏聚。
关键词:
双相钢
,
boron
,
hardenability
,
tensile property
陈国胜
,
金鑫
,
周奠华
,
王世普
,
谢伟
,
王林涛
金属学报
在晶界面上用萃取碳复型技术研究了镍基合金GH4049
(Ni-15Co-10Cr-5.5W-5Mo-4.2Al-1.5Ti)中与B和C的晶界
偏聚效应密切相关的二次析出相特征. B含量低于0.008%时, 因固溶
B/C(原子比)很低, 晶界析出大尺寸MC薄膜和M6C枝晶片以及薄膜状
M23C6, 不利于高温塑性和持久寿命. B含量为0.011%和
0.018%时, 固溶B/C(原子比)虽仅为0.667和0.941, 已可减少和全部
抑制上述碳化物的析出, 代之以弥散M3B2颗粒, 高温性
能大幅度上升. 但B含量过高, M3B2密集析出, 高温性能
下降. 降低固溶冷却速度而使B和C原子向晶界长程偏聚, 可促进
M3B2析出, 改善MC的形貌并抑制M6C和M23C6析出.
关键词:
镍基高温合金
,
boron
,
precipitate at grain boundary
YU Zongsen CHEN Ning University of Science and Technology Beijing
,
Beijing
,
China
金属学报(英文版)
Mechanism for diffusion of B in γ-Fe is believed to be mainly by means of boron-vacancy complexes other than as interstitial atoms previously.This was made of calculation on the ba- sis of theoretical model proposed by the authors.The calculated diffusion coefficient of B in γ-Fe after this mechanism is consistent with the experimental values.In addition,this is also supported by the non-equilibrium segregation phenomenon of B at grain boundaries of γ-Fe and the lattice constant measurement of Fe-B alloy.
关键词:
boron
,
null
,
null
,
null
,
null
X.H Luo
,
T.J. Su
,
C.G Fan
,
Y Y Liand CX Shi(Institute of Metal Research
,
Chinese Academy of Sciences
,
Shenyang 110015
,
China)X Chen and A.M Guo (Iron & Steel Research Institute
,
Wuhan Iron & Steel (Group) Company
,
Wuhan 430083
,
China)
金属学报(英文版)
1.25Cr-0.5Mo steels with different Ti-B or Al-B treatment were exposed in 18 MPa hydrogen atmosphere at 480℃ fo f 100, 500 and 1000 h respectively. Tensile and bend properties of steels before and after hydrogen changing were tested. The results show that the different mechanical properties of the steels with different B content have different responses to high temperature high pressure hydrogen charging processes.After hydrogen changing, more loss of ductility can be found in the steel not treated with B than those in the steels treated with B. Metallographic analyses indicated that decarburization occurred in all the steels. Furthermore, many methane bubbles were found by SEM analysis in the surface decarburization layer in the steel without B,while only a few bubbles, the number and size of which decreased with increasing B content, were found in steels with B treatment. In addition, hydrogen determination results manifested that after being exposed in hydrogen atmosphere the steel containing no B had higher hydrogen content than that of steels containing B. All this suggests that B treatment improved the HA resistance of 1.25Cgr-0.5Mo steel, and the more B the steel contained the more perceptible the effect.
关键词:
boron
,
null
,
null
,
null
P. Wu
金属学报(英文版)
The development of non-equilibrium segregation of boron at grain boundaries in Fe-40%Ni alloy during continuous cooling process was experimentally observed with boronParticle Tracking Autoradiography (PTA) and Transmission Electron Microscopy(TEM). The samples with 10ppm boron were cooled at 2℃/s to 1040, 980, 920,860, 780 and 640℃ respectively after pre-heat treatment of 1150℃ for 15min witha Gleeble-1500 heat simulating machine, then water quenched to room temperature.The width of segregation layer and boron depletion zone, rich factor and other pc-rameters were measured by a special image analysis system. The experimental resultsof PTA show that the grain boundary segregation of boron during cooling process is adynamic process and the development of the non-equilibrium segregation experiencesthree stages: first increases rapidly from 1150 to 1040℃, then gently from 1040 to860℃, and rapidly again from 860℃ to 640℃. The width of boron depletion zoneincreases from about 11μm at 1040℃ to 26μm at 640℃. TEM observation showsthat boron precipitates exist at grain boundaries when the samples are cooled to below860℃. The experimental phenomena are briefly discussed.
关键词:
boron
,
null
,
null
黄间珍
冶金分析
doi:10.13228/j.boyuan.issn1000-7571.009952
采用盐酸和过氧化氢溶解样品,选择B 249.678 nm、Bi 306.771 nm、Cd 228.802 nm、Co 228.615 nm、Ga 294.363 nm和Li 670.783 nm为分析线,使用基体匹配法绘制校准曲线消除基体效应的影响,采用电感耦合等离子体原子发射光谱法(ICP-AES)测定硼、铋、镉、钴、镓、锂,从而建立了铝合金中微量杂质元素硼、铋、镉、钴、镓、锂同时测定的方法.各元素的质量浓度在一定范围内与其发射强度呈线性,相关系数均大于0.999 8;方法检出限为0.1~3.7 μg/g.按照实验方法测定铝合金样品中硼、铋、镉、钴、镓、锂,结果的相对标准偏差(RSD,n=8)小于5%,回收率在94%~106%之间;实验方法用于测定3个铝合金标准样品中硼、铋、镉、钴、镓、锂,测定值和认定值相符合.
关键词:
电感耦合等离子体原子发射光谱法(ICP-AES)
,
铝合金
,
硼
,
铋
,
镉
,
钴
,
镓
,
锂
