深拉伸用钢:第一部分
非铁合金的热机械处理(TMT):第一部分
DataPLUS 模块提供上万种金属材料和非金属材料的腐蚀数据、焊接性能、尺寸与公差信息以及涂层信息。 点击这里了解更多。
Overview of Total Materia database 2022 年 1月 12日
Overview of Total Materia database 2022 年 1月 13日
在使用Total Materia几个月之后,以及深刻体验过所有潜在功能之后,我非常感谢你们的卓越工作和持续稳定的升级服务。 Total Materia始终是用来达成这一目的唯一工具。
M. Manfredini Bonfiglioli Industrial Gearmotors 博洛尼亚, 意大利
我们的目标很简单,就是让 Total Materia成为全球工程师在材料领域的首选一站式解决方案
Prof. Dr. Viktor Pocajt, CEOKey to Metals AG
Vanadium forged steels have found their place in industry sectors such as automotive to help combat some specific problems related to the quenching process of medium carbon steels. Alloying with vanadium has meant that advantageous properties such as tensile strength and yield stress can be achieved through air cooling of the material.
In automobiles and many other engineering machines, large quantities of components are made from forging steels. These parts are traditionally hot forged into their rough shapes and then quenched and tempered (Q+T) to obtain desirable mechanical properties.
Common applications include a variety of engine, transmission, suspension, and driveline components such as gears, springs, crankshafts, connecting rods, axles, spindles, etc. In most cases, these applications use microalloy precipitation for strengthening and/or grain refinement. The fundamentals of the precipitation and/or grain refinement are reviewed briefly. Differences encountered among the various applications stem from their different service requirements, which drive the use of different steel compositions and base microstructures (ferrite, pearlite, bainite, or martensite).
Traditional medium carbon forging steels achieve their strength and toughness in additional separate processes of quenching and tempering after forging. In order to reduce production costs and avoid usual problems associated with quenching, especially long products, vanadium microalloyed forging steels had been developed. These steels achieve required level of strength during air cooling directly from hot forging temperature, due to V(C, N) precipitation in ferrite.
However, the toughness of the air cooled steels is lower, because coarsening of austenite grains at temperatures used in conventional forgings produces coarse ferrite-pearlite structure. Microalloying with titanium provided austenite grain refinement by Zener pinning effect of highly insoluble TiN particles. Fine ferrite-pearlite structures with improved toughness had been achieved. On the other hand, coarse TiN particles, usually larger than 1 µm, act as fracture nucleation sites and are detrimental to the toughness of the steel.
The authors M.I.Equbal, R.K.Ohdar, B.Singh, P.Talukdar have studied the applicability of medium carbon vanadium micro-alloyed steel in hot forging. Forgeability has been determined with respect to different cooling rates, after forging in a hydraulic press at 50% diameter reduction in temperature range of 900-1100°C.
Data shown in Table 1 for ultimate tensile strength (UTS), yield strength (YS), percentage elongation (%EI), hardness (HV) and Charpy V- notch impact strength (CVN I.S.) with respect to different forging temperatures can be compared for normal air cool (NMA), forced air cool (FMA) and oil quenched (QMA) micro-alloyed steel.
On the other hand, the evaluations of the microstructure for 38MnVS6 microalloyed forged steel under various above mentioned cooling conditions are shown in Figure 1. Micro structural analysis indicates that NMA and FMA consist of ferrite-pearlite structure but QMA additionally contains some amount of bainite, alloyed cementite, vanadium carbides or carbo-nitrides. It has been observed that fine vanadium carbides or carbo-nitrides are distributed throughout the matrix of NMA, FMA and QMA steels.
As conclusion the author’s pointed out that:
References 1. L.Yang, A.Fatemi: Deformation and fatigue behavior of vanadium – based microalloyed forging steel in the as-forged and Q+T conditions, Journal of testing and evaluation, JTEVA, Vol.23. No2, March 1995, p.80-86; 2. C.J. van Tyne, D.K.Matlock, J.G.Speer: Microalloyed Forging Steels,Colorado School of Mines, IFC 2008, p.189-197; 3. D. M. Glišić, A. H. Fadel, N. A. Radović, Dj. V. Drobnjak, M. M. Zrilić: Deformation behaviour of two continuously cooled vanadium microalloyed steels at liquid nitrogen temperature, Hem. Ind. 67, (6), 2013, p.981–988, doi: 10.2298/HEMIND121214015G; 4. M.I.Equbal, R.K.Ohdar, B.Singh, P.Talukdar: Forgeability Study of Medium Carbon Micro-Alloyed Forging Steel, World Academy of Science, Engineering and Technology International Journal of Chemical, Molecular, Nuclear, Materials and Metallurgical Engineering Vol.9, No3, 2015, p.455-459;
Date Published: May-2017
输入搜索词:
搜索项
全文 关键字
标题 摘要
The Total Materia database contains a large number of metallography images across a large range of countries and standards.
Using the specifically designed Metallography tab in the menu bar, you can select the material of interest to you from the list of materials with metallography data included.
Metallography data can also be found through our standard quick search and will show relevant data is available through the standard Subgroup page for the material of interest.
Simply enter your material designation in to the "Material" field and select the standard of interest if known, then click "Search".
General information on microstructure can be found along with the relevant chemical composition for the material of interest.
Where available, a series of images will be provided showing a range of structural detail at various levels of magnification.
It is also possible to select different condition options from the "Select condition" drop-down to show metallography images under different process and heat treatment states.
For you’re a chance to take a test drive of the Total Materia database, we invite you to join a community of over 150,000 registered users through the Total Materia Free Demo.