全文获取类型
收费全文 | 566篇 |
免费 | 39篇 |
国内免费 | 53篇 |
专业分类
综合类 | 21篇 |
化学工业 | 6篇 |
金属工艺 | 212篇 |
机械仪表 | 22篇 |
矿业工程 | 4篇 |
能源动力 | 3篇 |
石油天然气 | 1篇 |
武器工业 | 1篇 |
无线电 | 8篇 |
一般工业技术 | 120篇 |
冶金工业 | 257篇 |
自动化技术 | 3篇 |
出版年
2024年 | 1篇 |
2023年 | 8篇 |
2022年 | 17篇 |
2021年 | 16篇 |
2020年 | 26篇 |
2019年 | 34篇 |
2018年 | 22篇 |
2017年 | 19篇 |
2016年 | 17篇 |
2015年 | 29篇 |
2014年 | 30篇 |
2013年 | 46篇 |
2012年 | 50篇 |
2011年 | 78篇 |
2010年 | 31篇 |
2009年 | 36篇 |
2008年 | 38篇 |
2007年 | 34篇 |
2006年 | 44篇 |
2005年 | 23篇 |
2004年 | 26篇 |
2003年 | 15篇 |
2002年 | 9篇 |
2001年 | 2篇 |
2000年 | 1篇 |
1999年 | 2篇 |
1995年 | 2篇 |
1994年 | 1篇 |
1989年 | 1篇 |
排序方式: 共有658条查询结果,搜索用时 15 毫秒
1.
主要研究了Cr对低碳Si-Mn系TRIP钢组织与力学性能的影响。首先利用Formastor-F型膨胀仪测定了含Cr和不含Cr两种低碳钢的连续冷却转变(CCT)曲线,分析指出了Cr对连续退火工艺的潜在影响;然后采用Gleeble-3800热/力模拟试验机对两种钢的薄板试样进行了连续退火模拟实验,并通过拉伸试验测定了力学性能;最后采用金相、扫描电镜、X-射线衍射分析等技术考察分析了两种钢的显微组织。结果表明:含Cr的TRIP钢的组织比较细小,铁素体晶粒近似等轴分布;两种TRIP钢的残余奥氏体含量相近,但含Cr钢的残余奥氏体中的含碳量较高。分析认为这是由于含Cr钢在热轧阶段较易生成细小的组织,而在热处理阶段则抑制贝氏体的生成,最终获得稳定的残余奥氏体。 相似文献
2.
The final microstructure of DP and TRIP assisted steels can evolve after hot working (hot rolling) or during post heat treatment process. In the formation of the final structure a number of different technological parameters have important roles, e.g. end temperature of rolling, cooling rates, temperature of intercritical annealing, etc. As a result of the individual factors and their combinations a lot of product technology routes are feasible. The effect of the different combinations of these technological parameters on the microstructure can be mapped by the special Jominy end-quench test (so called intercritical Jominy end-quench test) described in this paper. Unlike the traditional Jominy test, in this case there is a partial anstenizing between A1 and A3 temperatures which results in a given amount of ferrite in the microstructure before quenching. The method developed can be applied for mapping DP and TRIP assisted steels' microstructure in a wide range of technological parameters. The analysis of measured and calculated data can help us find the technological parameters optimal from the microstructural point of view. 相似文献
3.
Effects of Austempering after Hot Deformation on the Mechanical Properties of Hot Rolled Si-Mn TRIP Steel Sheets 总被引:1,自引:0,他引:1
LIZhuang ZHANGPing-li WUDi 《材料热处理学报》2004,25(5):248-251
Excellent mechanical properties are obtained by austempering after hot deformation without subsequent heat treatment in the present Si-Mn TRIP steel sheets. Isothermal holding time after finishing rolling has affected the mechanical properties of this steel. The results show that the sample exhibits a good combination of ultimate tensile strength and total elongation when it is held at the bainite transformation temperature after hot deformation. The stability of retained austenite increases with an increase of isothermal holding time, and a further increase in the holding duration results in a decrease of it. The tensile strength, total elongation and strength ductility reach the maximum values (774MPa, 33% and 25542MPa% respectively) for this sort of hot rolled Si-Mn TRIP steel using the optimal technology. 相似文献
4.
李洪洋 《武汉理工大学学报(材料科学英文版)》2014,29(3):594-600
To investigate the transformation behavior of TRIP steel retained austenite under cyclic load, cyclic V-bending deformation of low carbon Si-Mn TRIP600 was studied by experiment and finite element in this paper. The results showed that, under cyclic V-bending deformation, retained austenite in TRIP steel transformed into martensite gradually with the increasing of bending times, and for the symmetrical characteristic, upper surface and lower surface presented the same transformation tendency. From the first to the fourth V-bending deformatiort, retained austenite volume fraction decreased nearly linearly and then attained saturation step by step. Compressive stress state was helpful for martensite transformation than tension stress state with V-bending deformation, and strain magnitude was the determining factor for retaining anstenite martensitic transformation. With the increasing of bending times effective stress increased and the relationship between maximum effective stress and bending times was nearly linear. Effective stress and effective strain distribution were non-uniform, the maximum effective stress and effective strain were present in the center of the samples. The relationships between retained austenite and V-bending times, and retained austenite with effective strain were set up as Eqs.(1)-(5). The relationship was typical quadric function, decreased linearly for the initial deformation and attained saturation finally. 相似文献
5.
低碳Si-Mn系TRIP钢的热处理工艺对组织的影响 总被引:15,自引:2,他引:15
低碳Si-Mn系TRIP钢有着复杂的显微组织,主要由多边形铁素体(F)+无碳贝氏体(B)+残留奥氏体(AR)组成。本试验采用了彩色金相法,并结合X-ray衍射、SEM和TEM等手段研究了低碳Si-Mn系TRIP钢显微组织与工艺的关系,发现随着两相区退火温度的升高,最终显微组织中铁素体基体体积分数变小,并且贝氏体量增多,残留奥氏体的稳定性呈起伏式变化;在贝氏体转变区的等温温度过高或过低,均使最终显微组织中残留奥氏体体积分数减少;在贝氏体转变区等温时,所形成贝氏体表现出粒状的特征。 相似文献
6.
7.
Cold-rolled and annealed ultra-high strength sheet steels with good ductility accompanied by TRIP of retained austenite have
received considerable attention in recent years. This paper discusses the effect of silicon content and annealing temperature
on the formation of retained austenite and the mechanical properties in Fe-0.34%C-1.7% Mn steels whose structure consists
of ferrite, bainite and retained austenite. Silicon inhibited the cementite formation in bainite during isothermal holding
and partitioned carbon from bainite to austenite, resulting in an increase in retained austenite content. When the silicon
content was increased to 1.0 wt.% or higher, the amount of retained austenite markedly increased leading to good mechanical
properties. 0.34%C-1.03%Si-1.7%Mn steel showed a high tensile strength of 1,030 MPa and a total elongation of 34.5% when annealed
at 780°C for 5 min followed by isothermal holding at 400°C for 5 min. In this case, the amount of retained austenite was about
25%. The variation in tensile strength-elongation combination had good correlation with that in the amount of retained austenite
with both annealing temperature and silicon content. The most retained austenite was obtained in the steel annealed at just
above AC1 temperature. The annealing temperature which gives the most retained austenite was decreased with decreasing the silicon
content. 相似文献
8.
9.
10.
The presence of ferrite/pearlite bands in dual phase and TRIP assisted steels is a consequence of microchemical segregation which causes mechanical properties anisotropy. Such inhomogeneous phase distribution produces a lowering of the mechanical properties such as fracture behaviour. This anisotropy is commonly not accounted in micromechanics computations which often assume a random distribution of phases in the solid. The present paper deals with an integral model for this undesirable band formation accounting for the solute segregation caused by solidification, microcomponent diffusion present in the austenitisation process, and the nucleation of the transformed phase in segregated regions. In the present work, the model was applied to two industrial grade dual phase steels and two TRIP assisted steels. The influence of such parameters on band formation is summarised in a number of “band prevention plots”, which are aimed at providing the optimum processing conditions for ferrite/pearlite band prevention. 相似文献