YU Wei
,
QIAN Ya-jun
,
WU Hui-bin
,
YANG Yue-hui
钢铁研究学报(英文版)
Two types of steel, C-Mn-Cr-Mo-B microalloyed steel and C-Mn-Mo-Nb-Cu-B microalloyed steel, are designed to develop 1000 MPa ultra-high strength steel. Two kinds of processes, thermomechanical controlled process (TMCP) combined with traditional off-line quenching and tempering (QT) process versus controlled rolling process (CR) combined with direct quenching and tempering (DQ+T) process, are applied. The effect of heat treatment processing mode on the microstructure and mechanical properties is studied. The relationship between microstructure and mechanical properties is investigated by SEM and TEM. After tempering at 450 to 550 ℃ for 1 h, the steel produced by TMCP+QT process shows combination of excellent strength and low temperature toughness. The yield strength is above 1000 MPa, elongation above 15% and impact energy at -40 ℃ more than 30 J. After tempering at 450 ℃, a large number of ε-Cu particles precipitated in C-Mn-Mo-Nb-Cu-B steel produced by CR+DQ+T process lead to a significant increase in yield strength. And after tempering at 500 to 600 ℃, the yield strength of the steel is further improved to 1030 MPa because of precipitates, such as nitride or carbide of niobium, carbide of molybedenum and vanadium. When the tempering temperature is increased above 620 ℃, the yield strength is still higher than 1000 MPa and elongation is above 20% and impact energy at -40 ℃ is more than 35 J. After tempering at above 500 ℃, the toughness of the steel treated by TMCP+QT process is superior to that of steel by CR+DQ+T process.
关键词:
Heat treatment, High strength steel, Microtructures, Mechanical properties
宋育来
,
陈吉清
,
陈邦文
,
刘静
,
刘志勇
,
胡敏
钢铁研究
研究了集装箱用SM490YA钢板的力学性能、工艺性能、微观组织结构等.采用气体保护焊对钢板进行焊接性能试验评价,并对钢的强韧化机理进行初步探讨.结果表明,SM490YA钢板不仅性能稳定,不存在明显的各向异性,易于成型,而且钢板焊接性能优良,是制造集装箱的理想钢板.
关键词:
集装箱钢
,
力学性能
,
工艺性能
,
焊接性能
,
微观组织
林元华
,
张中太
,
张枫
,
唐子龙
,
吕霄
,
郑子山
功能材料
利用SrCO3-A12O3-RE(NO3)3(RE:Eu,Dy)粉体为原料,加入少量酒精,进行预混合、球磨、干燥.将此混合粉体在还原气氛下高温烧成,最终制得不同发光性能的xSrO.yAl2O3:RE(RE:Eu,Dy)光致发光材料,并对其性能进行了研究.发光粉体的发射光谱表明,随着A12O3/SrO(摩尔比x)的增加,其相应粉体发射光谱的主峰位置(λE)逐渐向短波方向移动,符合λE=531.018-23.028X关系式.余辉衰减曲线表明,这些发光材料均具有一定的长余辉特性.从而说明只要控制一定的Al2O3/SrO比例,即可获得发光颜色为紫色到绿色的多种发光材料.对于其长余辉机制,认为是加入的Dy3+起到了陷阱能级的作用,它将部分空穴俘获,并在热扰动下,慢慢将空穴释放出来,并再次与介稳态Eu1+复合发光,从而达到延长余辉的作用.
关键词:
长余辉
,
发光材料
,
发射光谱
,
空穴
胡海龙
,
曾宇平
,
左开慧
,
夏咏锋
,
姚冬旭
无机材料学报
doi:10.15541/jim20140181
分别以Y2O3-Al2O3(YA)和Y2O3-MgO(YM)为烧结助剂，采用气压烧结工艺制备了Si3N4/SiC陶瓷，研究了两种不同的烧结助剂对陶瓷的力学和摩擦性能的影响。研究结果表明：添加不同种类的烧结助剂对制备陶瓷的相对密度、抗弯强度、断裂韧性、硬度、摩擦系数和磨损率影响很大；与添加烧结助剂YM相比较，添加烧结助剂YA的Si3N4/SiC陶瓷在烧结过程中表现出了更好的烧结性能，得到的陶瓷样品最终显示了更好的力学和摩擦性能，尤其是SiC添加量为20wt%的Si3N4/SiC陶瓷。这主要归因于烧结助剂YA的添加使Si3N4/SiC陶瓷呈现出了更高的相对密度，获得的晶粒长径比更小。
关键词:
Si3N4/SiC陶瓷
,
烧结助剂
,
抗弯强度
,
摩擦性能
LI Chong-wei
,
CHENG Guo-guang
,
WANG Xin-hua
,
ZHU Guo-sen
,
CUI Ai-min
钢铁研究学报(英文版)
A mathematical model in present study has been established to investigate the effect of Rheinstahl Heraeus (RH) blow argon mode on the decarburization rate in ultra-low carbon steel refining based on the RH equipment of Shougang Qian′an Iron and Steel Co Ltd (SQISCO). The calculated results show that the increase of argon flowrate promotes the carbon elimination from argon gas bubble surface, molten steel free surface in vacuum as well as splash droplet surface, while reduces that from the interior of liquid steel. It has been found the critical turning point of flowrate ascension is at the 5th minute and the optimum blow argon flowrate in later stage is 2100 L/min in accordance with the 2 stages argon blow mode, which have been confirmed in the commercial production in SQISCO.
关键词:
RH
,
vacuum
,
mathematical model
,
argon flowrate
,
decarburization
孔凡涛
,
陈玉勇
,
李宝辉
金属学报
铸态Ti-43Al-9V-0.3Y合金由γ相及少量α2, B2和YA2相组成,
为细小的近层片组织, 晶粒(层片团)尺
寸约为80 um, 层片体积分数约为85 %; 锻态合金由大量细小的动态再结晶等
轴γ晶粒组成, 组织细化显著, γ再
结晶晶粒尺寸约为1-5 um; 轧态合金为细小近γ组织, γ晶粒尺寸约为20um, 尺寸细小的B2相呈网络状分布在γ晶粒周围. 铸态合金在室温下的拉伸断裂强度约为510.6 MPa, 延伸率约为0.5%; 在700 ℃下的拉伸断裂强度约为425.8 MPa, 延伸率约为5.7%. 锻造和轧制后的Ti-43Al-9V-0.3Y合金的力学性能均得到了明显改善.
关键词:
Ti-V-Y合金
,
processing technology
,
microstructure
,
tensile properties
,
null
张昕
,
廖晶莹
,
谢建军
,
沈炳孚
,
邵培发
,
李长泉
,
袁辉
,
殷之文
无机材料学报
doi:10.3321/j.issn:1000-324X.2002.05.005
Y3+离子掺杂钨酸铅晶体特殊的低剂量率辐照行为一般在晶体顶端表现更为明显,以往研究认为该现象起因于晶体中有效分凝系数＜1的Na+、K+和Si4+等杂质在顶端的富集.本文研究了Si4+掺杂的Y3+:pwO晶体,对晶体顶端和晶种端的分段晶体测试了退火温度对晶体透过率和辐照硬度的影响,结果发现:在实验所涉及的掺杂浓度范围内,Si4+离子杂质对Y3+:pwO晶体的辐照硬度及透过率无影响,可以认为Ya+:pWO晶体特殊的低剂量率辐照行为和晶体中的Si4+离子含量无关.
关键词:
钨酸铅
,
掺杂
,
辐照硬度
,
闪烁性能
