都祥元苏国跃
金属学报
doi:10.3724/SP.J.1037.2011.00209
通过优化设计与控制C, Ni, Cr主合金元素和H, O, N气体元素含量, 优化管材冷轧工艺, 有效防止了1Cr13管材加工时的开裂现象, 保证了管材表面质量良好; 通过调整成品热处理工艺, 使试制的管材样件的力学性能完全满足了技术条件要求.
关键词:
1Cr13钢
,
tube
,
cold rolling
,
heat-treatment
王东马宗义
金属学报
doi:DOI: 10.3724/SP.J.1037.2009.00723
7050铝合金固溶处理后经67%冷变形, 在120 ℃一级时效时, 冷轧引入的大量位错增加了样品强度, 时效4 h样品的强度比T6状态样品提高12.6%. 随时效时间增加, 位错导致的不均匀形核的析出相粗化, 样品的拉伸强度逐渐降低. 但时效32 h样品的强度仍高于T6状态样品. 冷轧后时效样品的晶界析出相与T6状态相比分布较为分散, 并且随时效时间的增加逐渐粗化. 120 ℃时效4 h的样品, 经165 ℃二级时效处理, 随时效时间的增加, 样品中残留位错大量湮灭, 晶内、晶界析出相尺寸均逐渐增大, 导致样品的强度逐渐降低, 而延伸率逐渐升高, 165 ℃时效6 h样品的强度与T76样品相似. 在135-180 ℃二级时效1 h的样品中的位错密度随温度的升高而减小, 同时晶内、晶界析出相尺寸随温度的升高而增大, 导致样品强度逐渐下降.
关键词:
7050铝合金
,
cold rolling
,
aging process
,
mechanical property
,
microstructure
孙淑华
,
熊毅
,
傅万堂
,
邢广忠
,
古原忠
,
牧正志
金属学报
用SEM、TEM及XRD等方法研究了共析钢中珠光体经40%—90%的冷轧变形后所产生的显微组织变化. 按渗碳体形态特点, 变形珠光体组织可分为以下3种类型: (1) 不规则弯曲片层型, 即变形后的渗碳体与轧制面呈大角度偏离且不规则弯曲的珠光体. (2) 带有剪切带的粗大片层型，即被渗碳体剪切带分开且变形轻微的珠光体. (3) 精细片层型，即与轧制方向平行排列、片间距细小且渗碳体严重变形的珠光体. 精细片层区域的比例随着轧制压下率的提高而增大. 此外，重度冷轧变形还引起渗碳体严重塑性变形和部分溶解.
关键词:
高碳钢
,
pearlite
,
cold rolling
吴桂林
,
刘伟
,
A.Godfrey
,
刘庆
金属学报
原始取向为001uv0的柱状晶Al样品分别冷轧到10%, 30%和50%, 采用EBSP技术定量表征了不同取向晶粒基带内的微观分裂. 结果表明晶粒均都分裂为胞块组织, 不同取向晶粒变形后的微观组织结构不同.
随应变量的增加GNBs取向差增加, 并满足23指数关系.Frank公式分析表明, 胞块界面中的位错主要来自由Schmid因子决定的激活滑移位错.
关键词:
柱状晶Al
,
cold rolling
,
EBSP
吴桂林
,
刘
,
伟
,
A.Godfrey
,
刘庆
金属学报
原始取向为001uv0的柱状晶Al样品分别冷轧到10, 30和50, 采用EBSP技术定量表征了不同取向晶粒的宏观分裂, 结果表明, 不同取向晶粒在轧制过程中的分裂模式不同. 利用位错滑移模型合理地解释了观察到的宏观分裂时的晶体转动.
关键词:
柱状晶Al
,
cold rolling
,
EBSP
X. Zhang
,
C.X. Wang
,
X.M. Liu
,
Q.N. Shi
金属学报(英文版)
The microstructure evolution of different cold rolling reductions （from 0 to 81.6%）is studied by SEM (scanning electron microscopy) and TEM (transmission electron microscope). The study showed that the orientation multiplicity of pearlitic lamellas resulted in inhomogeneous deformation of different pearlitic lamellas, and with the increase of reduction, the microstructure underwent a course of "homogeneity → inhomogeneity → homogeneity". The result of XRD (X-ray diffraction) analysis indicated that cementite did not decompose and dissolve into ferrite; the results of the mechanical property test suggested that the relationship between Rp0.2 (yield strength) and ε (true strain) is in good agreement with Hollomon relationship. With the equation Rp0.2 = 1465ε0.18, the yield strength of the steel in different reductions could be well predicted.
关键词:
cold rolling
,
null
,
null
,
null
WU Guofa XU Zhe ZHUO Bing Central Iron and Steel Research Institute
,
Beijing
,
China.
材料科学技术（英）
The optimal control principle and procedure of a tandem cold rolling system for tracking problem have been proposed in this paper for the first time. The state-space description of the tandem cold rolling system for the cold-strip mill of Wuhan Iron and Steel Company is: x_(k+1)=Ax_k+(_k,y_k=Cx_k+η_k The optimum performance index of the system for tracking problem is: J_(min)=minEr[(1/2)sum from k=0 to m e'_kOe_k sum from k=0 to m-1 u'_kRu_k] The authors have deduced the optimal control of the system for tracking problem as follows u_k~*=-S_k(Ay_k+_(k+1)-) the feedback gain matrix S_k is given by S_k=(B'P_(k+1)B-R)~(-1)B'P_(k+1) Pk satisfies the matrix difference equation p_k=P_(k+1)-[(S_k~(-1))'-B']~(-1)R(S_k~(-1)-B)~(-1)+Q with terminal condition P_m=Q. On the above-mentioned principle of optimal control,an optimal control procedure of the tandem cold rolling system has been obtained, and a computer simulation has been performed. The results of the simulation are satisfactory.
关键词:
optimal control
,
null
,
null
,
null
null
,
null
金属学报(英文版)
Mg-9wt%Li-2wt%Zn alloy was prepared and studied in this article. The addition of Ca to the alloy from 0.1wt% to 1wt% can refine the α-Mg and the best effect of refinement occurs when Ca content is 0.4wt%-0.5wt%. The billets can be rolled to thin sheets at room temperature, from which it is obvious that the addition of Ca improves alloys' formality, while it decreases with the excess addition of Ca. The results also show that the ultimate tensile strength (UTS) and yield strength (YS) of the alloy with 1wt% Ca may rise by 28% and 25%, respectively, however, the elongation decreases. It is clarified that the adsorption of proper Ca on the grain boundaries refines α-Mg and improves the tensile properties, but the presence of excess Ca and stable Ca2Mg6Zn3 phase worsens the elongation.
关键词:
calcium
,
null
,
null
冯喜奎
,
贾华坡
,
任毛丁
硬质合金
doi:10.3969/j.issn.1003-7292.2016.06.007
钢的异型小截面冷精轧在纺织器材、金属制品、线材加工等行业被广泛应用.为了有效解决此类冷精轧硬质合金轧辊高发损伤这一棘手的难题,归纳了此类冷精轧的特点,展示了其高速轧机的轧头结构,指出此类轧辊的高发损伤形式为爆点、毛边棱、边角垮塌、崩落扩展沟和断裂,突出特点是损伤的快速扩展.从材质的变形抗力、轧制强度、轧辊材质特性三个主要方面分析了所用复合式硬质合金轧辊损伤及扩展的诱因、形式及特点.指出抑制硬质相晶粒异常长大,提高强韧性,消除微观缺陷是前提.提高轧制系统精度,优化轧制工艺,完善轧机生产辅助条件,强化操作规范与技巧则是生产实践中控制轧辊损伤、降低轧辊耗用量的有效对策.
关键词:
硬质合金
,
轧辊
,
损伤
,
爆点
,
磨损
,
冷轧
,
变形抗力
李志峰
,
麻永林
,
冯岩
,
宫美娜
,
邢淑清
钢铁
基于现场生产冷轧极薄不锈钢带材表面硬度极难控制的问题,针对301S不锈钢的冷轧生产工艺进行了研究,分析了不锈钢冷轧生产过程中影响表面硬度的相关工艺参数,得出材料的抗拉强度、轧制速度、轧制油温度和压下率是影响轧后材料表面硬度的关键因素.利用BP神经网络建立了预测表面硬度的非线性映射模型,并根据此模型得出了预测数据的趋势图谱.研究结果表明,压下率的变化对冷轧不锈钢表面硬度的调节能力最强,而其他参数对硬度的影响为10HV左右.经检验,模型的预测值和实测值的相对误差为-2.63％～2.76％,预测结果准确率高,可以用于产品质量的现场在线控制.
关键词:
冷轧
,
不锈钢
,
神经网络
,
工艺参数
,
硬度预测
