Z.Q. Sheng and H. Xiao(National Key Laboratory for Nuclear Fuel and Material
,
Nuclear Power Institute of China
,
Chengdu 610041
,
China)Manuscript received in revised form 16 October 1998)
金属学报(英文版)
By means of TEM technique the orientation relationships of cementite, precipitated from islands of granular bainite during tempering, with ferrite have been objerved. By calculating the eigenvalue and eigenvector of transformation matrix, Isaichev relationship has been analyzed. The results indicate that Isaichev relationship indeed is the sum of Kungumov-Sachs relationship and Pitsch relationship, so the viempoint that the cementite with Isaichev relationship precipitates from austenite, instead of ferrite,is confirmed. Moreoven the matrix calculation shows that three reported orientation relationships among austenite, ferrite and cementite in pearlitic transformation cannot be simultaneously valid.
关键词:
orientation relationship
,
null
张强
,
许少普
,
李忠波
,
唐郑磊
,
高照海
,
杨阳
钢铁
doi:10.13228/j.boyuan.issn1001-0963.20150135
采用横截面为350mm×2 320 mm的钢坯轧制横截面为100 mm×2 360 mm的Q345E-Z35.在粗轧阶段以高于动态再结晶临界变形量和形状系数l/h≥0.53的条件下,经过不同的终轧温度和返红温度试验,最终确定精轧阶段终轧温度控制在780℃左右,返红温度控制在610℃左右,生产出的钢板具有优异的力学性能和层状撕裂抗性.
关键词:
Q345E-Z35
,
特厚板
,
控轧控冷
WADSWORTH Jeffrey and FLUSS Michael(Chemistry and Materials Science Directorate
,
Lawrence Livermore National Laboratory
,
Livermore
,
CA 94551)
金属学报(英文版)
The role of the National Laboratories is summarized from the era of post World War II to the present time. The U.S. federal government policy for the National Laboratories and its influence on their materials science infrastructure is reviewed with respect to .determining overall research strategies, various initiatives to interact with industry (especially in recent years),building facilities that serve the nation, and developing leading edge research in the materials sciences. Despite reductions in support for research in the U.S. in recent years, and uncertainties regarding the specific policies for Research &Development (R&D) in the U.S., there are strong roles for materials research at the National Laboratories. These roles will be centered on the abilities of the National Laboratories to field multidisciplinary teams, the use of unique cutting edge facilities, a focus on areas of strength within each of the labs,increased teaming and partnerships, and the selection of motivated research areas. It is hoped that such teaming opportunities will include new alliances with China, in a manner similar, perhaps, to those recently achieved between the U.S. and other countries.
关键词:
: U.S. Materials Science. U.S. National Laboratories and Facilities
,
null
朱书成
钢铁研究学报
采用高倍金相检验、扫描电镜及能谱分析等方法对120mm Q390GJC-Z35特厚板的z向性能不合缺陷进行了研究。结果表明:z向性能不合主要是由于钢锭存在着较严重的中心偏析,在不合试样断口处存在着较多的块状(Nb、Ti)C聚集,块状的(Nb、Ti)C成为裂纹源。此外,偏析处还存在贝氏体等硬相组织,更加剧了断裂扩展,导致z向性能不合。通过优化成分设计,加强精炼过程控制,改进模铸浇注工艺,制定合理热处理工艺等相关措施,取得了良好的效果。
关键词:
Q390GJC-Z35
,
z向性能
,
不合
,
原因分析
,
措施
唐郑磊
,
张涛
,
杨东
,
李红洋
,
徐昭
,
庞林
钢铁研究
通过成分设计、轧制、热处理工艺设计,采用晶粒细化、固溶强化、析出强化等手段,对80、110mm的Q460GJC-Z35高强度钢板的研发工艺及过程进行试验设计。结果表明:通过Nb、V、Ti、Ni复合微合金化和控轧控冷、正火快冷(NAC)热处理相结合生产的模铸Q460GJE-Z35钢板具有晶粒细小、组织均匀,钢板屈服强度达到420~490 MPa,抗拉强度达到585~625 MPa,伸长率达到20%以上,0℃冲击功达到123 J以上,Z向断面收缩率大于35%,探伤达到1级探伤要求,实现了强度和韧性的良好匹配和较高的内部质量。
关键词:
Q460GJC-Z35
,
成分设计
,
热处理工艺设计
李虎
,
王作成
,
薛长深
,
庄栋栋
,
王晓
,
张思勋
材料热处理学报
为了研究钢中合金元素Nb、B、Ni对低合金高强度H型钢抗层状撕裂能力(Z向性能)的影响,设计了对照试验,通过常温下拉力试验,对其力学性能尤其是断面收缩率进行了测试,使用XRD、SEM、TEM以及EDS对其组织和成分进行了分析.结果表明:微合金元素Nb、B和微量元素Ni对钢材的Z向性能产生了明显的不良影响,含有Nb、B和Ni,经过钢包精炼的Q345E钢的Z向性能显著低于不含Nb、B和Ni,未经钢包精炼且含有较多夹杂物的Q345B钢.其原因主要在于Nb、B、Ni的存在阻碍了钢材变形过程中位错在晶界和晶内的移动.
关键词:
低合金高强度钢
,
Z向性能
,
合金元素
,
夹杂物
,
阻碍位错
唐郑磊
,
张涛
,
杨东
,
李红洋
,
徐昭
,
庞琳
钢铁
在生产试验的条件下,通过成分设计和轧制、热处理工艺设计,采用晶粒细化、固溶强化、析出强化等手段,对80、110、120mm厚的Q460GJE-Z35高强度钢板的研发工艺及过程进行了试验研究。结果表明:通过铌、钒、钛、镍复合微合金化和控轧控冷、正火快冷(NAC)热处理相结合生产的模铸Q460GJE-Z35钢板晶粒细小、组织均匀,强度和韧性匹配良好、内部质量较优。
关键词:
Q460GJE-Z35钢板
,
成分设计
,
正火加速冷却
朱书成
,
于飒
,
高照海
,
李忠波
,
袁永旗
钢铁
利用250mm连铸坯料,在3 800mm宽厚板轧机上针对Q345GJC-Z35钢种进行了厚50~80mm钢板的TMCP工艺试验,确定了相应的热轧及控冷工艺条件。结果表明:采用碳的质量分数低于0.11%添加微量复合铌、钒、钛元素,按照2阶段控制,当轧到成品钢板厚度的2~3倍时开始待温,精轧开轧温度小于860℃,终轧温度为820~860℃,生产的Q345GJC-Z35高强度厚板的性能完全超出国家标准GB19879—2005要求,而且其钢板的平均断面收缩率都大于50%,远高于Z35钢板的技术要求。实现了钢板很好的强韧性匹配,工艺上不用后续热处理,减少了工艺流程,节约了成本。
关键词:
Q345GJC-Z35钢
,
特厚钢板
,
控制轧制
,
Z向性能