交叉轧制对钼板材显微组织和成形性能的影响

本文采用力学性能测试、深冲测试、金相组织观察以及X射线宏观织构分析等实验手段,详细研究了交叉轧制对钼板材显微组织和性能的影响规律。研究结果表明,单向轧制钼板材的横向延伸率明显低于纵向延伸率,交叉轧制可明显降低钼板材力学性能的各向异性;交叉轧制使钼板材的杯突值显著提高,且使钼板材深冲时的开裂方向由单向轧制样品的横向开裂转变为交叉轧制样品的沿轧制方向45°开裂;交叉轧制钼板材的金相组织呈现出相互搭接交错的纤维状组织特征,且纵横向的组织差别较单向轧制钼板材明显减小;交叉轧制使钼板材的织构由强各向异性的旋转立方织构转变为各向异性较低的立方织构。     

工艺因素对铌带深冲性能的影响

研究了锻造开坯、轧制、热处理工艺对铌带深冲性能的影响.采用万能试验机、扫描电子显微镜对材料性能和微观形貌进行分析.结果表明:采用较高的锻造温度、较大的开坯压下量及低温长时间热处理,能使铌带具有更好的深冲性能、较高的强度和延伸率及良好的织构分布.铌带冷轧织构类型为典型的[100]//RD和[111]//ND纤维织构,经再结晶退火后转变为很强的(111)[101]到(111)[11(2)]的过渡型织构和较弱的(100)[011l]±15°织构.再结晶纤维织构强度大幅度增加,有利于消除深冲时的制耳.     

交叉轧制钼带冷深冲性能及微观组织研究

通过交叉轧制、冷深冲成形以及力学性能和微观组织分析,研究液晶显示器背光源用钼带冷深冲性能和微观组织演变。结果表明:采用两次低温交叉轧制和一次交叉冷轧工艺制备了高质量高冷深冲性能的0.2mm厚钼带,其具有较弱的各向异性和良好的力学性能;利用多道次连续冷深冲方法成功地制备了细小钼杯:Φ外2.0mm,H高10mm,钼杯整个断面微观组织呈纤维状细长晶粒且相互搭接交错,底部圆角处减薄量最大,即"危险区"。所研制的钼带适合于制备液晶显示器背光源发光体材料。     

织构预处理对高强IF钢性能的影响

研究了织构预处理工艺和常规工艺对高强IF钢组织性能的影响,结果表明,经过织构预处理的钢板退火组织更加均匀、细小,屈服强度基本不变,抗拉强度降低,伸长率升高,r值有较大幅度的提高,而且具有强烈的{111}〈110〉织构以及较强的γ纤维织构,深冲性能好。     

IF钢铁素体区轧制对带钢最终性能的影响

采用铁素体区轧制工艺能够大大提高IF钢冷、热轧带钢的深冲性能。本研究通过工业试验验证了铁素体区轧制工艺的可行性。试制带钢组织、织构及性能检测的结果表明：热轧带钢1/4厚度处和芯部初步形成了γ织构,连续退火冷轧带钢中形成了强烈的γ织构,冷轧带钢的伸长率达到50%以上,r值达到3.15,具有优良的成形性能。     

轧制方式对Mo-1钼板组织和性能的影响

研究轧制方式对Mo-1钼板组织和性能的影响,交叉轧制可使钼板的延伸率显著提高,σ0.2和σs明显下降,加强了组织的均匀性和等轴性。交叉轧制的Mo-1钼板具有良好的深冲性能。     

异步轧制对3004名合金变形织构及制耳率的影响

以３００４铝合金为实验材料，研究了异步轧制对该合金的变形织构以及相应的制耳率的影响。实验表明：异步轧制和同步轧制板的主要变形织构是相同的，均为纯铜型织构｛１１２｝〈１１１〉＋｛２１３｝〈３６４〉＋｛１１０｝〈１１２〉，但异步轧制产生的变形织构较同步轧制的强度高，且随异步轧制速比的提高而增加。同时，异步轧制的板材中还出现｛００１｝〈１１０〉织构。另外，在相同压下率的情况下，异步轧制板材的深冲制耳率大     

异步轧制速比对高纯铝箔织构转变的影响

采用不同速比对高纯铝板进行异步冷轧,并将冷轧样品进行不同温度和时间的再结晶退火,研究异步轧制速比对高纯铝箔织构转变的影响。结果表明:高速比的异步轧制在样品中产生较强的旋转立方织构和{102}〈uvw〉织构,异步轧制退火后的高纯铝箔样品具有很强的立方织构{001}〈100〉。立方织构的体积分数与速比和温度有关:当速比为1.06时,温度升至300℃开始出现立方织构;当速比为1.17时,温度升到200℃就出现立方织构。立方织构组分的形成存在一个阈值温度,此温度与异步轧制的速比成反比,随着速比的增加,阈值温度逐渐降低,这与异步轧制提高高纯铝箔的形变储能有关。异步轧制有利于在低温时形成较强的立方{001}〈100〉织构。     

热轧工艺对超薄规格冷轧IF钢织构及成形性能的影响

为了研究铁素体轧制和奥氏体轧制两种不同热轧工艺对超薄规格冷轧IF钢组织、织构和成形性能的影响,采用金相显微镜和XRD衍射仪分别观察和检测了两种热轧工艺下热轧、冷轧、退火带钢微观组织和宏观织构,采用EBSD检测了退火带钢的表面微观织构,采用拉伸试验机分别检测了退火带钢沿轧向、45°方向和横向的力学性能。结果表明：相比奥氏体轧制工艺,铁素体轧制工艺下退火带钢γ织构更强,主要织构组元{111}<110>、{111}<112>强度差异更小,相应■值提高0.45,△r值降低0.10;铁素体轧制工艺下冷轧带钢位错、亚晶界等晶体缺陷密度更大,且形成的α织构更强,退火过程中具备<110>//ND取向的晶粒优先形核,且在生长过程中吞并邻近低取向差的{118}<110>、{557}<110>等其他取向晶粒,从而导致退火板形成更强的{111}织构。     

轧制方式对La-TZM合金板材力学性能的影响

利用粉末冶金法制备了La-TZM合金,研究了轧制方式对合金板材力学性能的影响.结果表明,采用交叉轧制的方法可以使金属变形更加均匀,有效地减少板材的各向异性,得到纵、横向相同力学性能.不同温度退火态交叉轧制板材的室温抗拉强度和屈服强度比单向轧制有所下降,但伸长率显著提高;交叉轧制板材的再结晶温度低于单向轧制板的再结晶温度.     

Microstructure and Mechanical Properties of Molybdenum Sheet after Cross Rolling Processing

ALTHOUGH the molybdenum processing formanufacturing application has been studied for morethan 40 years, practical application of high-qualitymolybdenum products are limited. Molybdenum is arefractory metal that undergoes no phase change for thebcc crystal structure from the ambient to the meltingtemperature (2610 °C). Good high temperature strength,creep resistance, low coefficient of thermal expansion,and high thermal conductivity are attractive propertiesof pure molybdenum and molybdenum…     

Effects of cross rolling on texture,mechanical properties and anisotropy of pure Mo plates

To clarify the influence of the deformation texture on the mechanical properties, pure Mo plates were processed by various cross rolling procedures, and the relation among texture, microstructure and mechanical properties was discussed. The results show that cross rolling of the Mo plates is beneficial for the formation of the rotated cube component, i.e., {001}〈110〉. The corresponding orientation density exhibits a positive correlation with the total rolling deformation and the current-pass deformation. When the total deformation is 96% or greater, the Mo plates form a texture orientation dominated by {001}〈110〉, whereas the γ-fibre texture becomes weaker and the cube texture {100}〈100〉 disappears completely. The presence of {001}〈110〉 has great effects on the properties of cross-rolled Mo plates, which is beneficial for strength enhancement and plasticity reduction in both the rolling direction (RD) and the transverse direction (TD).     

Experiment investigation of deep-drawing sheet texture evolution

To ensure the deep-drawability of the deep-drawing sheet, the normal anisotropy and planar isotropy of the sheet is required. The drawing property of the sheet is controlled by its crystallographic texture, the type and orientation density of the texture directly influence the drawing-quality of deep-drawing sheet. {1 1 1}1 1 2 and {1 1 1}1 1 0 are the ideal textures for deep-drawing sheet, because the correct texture gives the proper orientation of slip system so that the strength in the thickness direction is greater than that in the plane of the sheet. During the production processing of the deep-drawing sheet, the development of crystallographic texture is continuous, and the final texture character of the product is determined by the texture evolution processing at the different technological process. In the present work, the whole production flow of a coiled sheet has been flowed in Benxi Iron and Steel (Group) Co., Ltd., and the samples were cut from this coiled sheet at the different production flow, such as after hot rolling, cold rolling and recrystallization annealing, respectively. The texture evolution processing has been investigated for the whole production flow of the deep-drawing sheet. Some factors that influence the evolution of the crystallographic texture have been analyzed, such as the grain size of hot-rolled sheet, the reduction ration in the cold rolling, the annealing process, the precipitation of AlN during the coiling and, etc. This paper centers on the research of the texture evolution in each different process. An optimum technique to improve the deep-drawability of the deep-drawing sheet has been put forward.     

唐钢冷连轧低碳薄板深冲性能的研究

采用唐山钢铁股份有限公司FTSR连铸连轧生产线生产的热轧卷作为生产冷轧低碳钢板的原料，研究了不同卷取温度和冷轧压下率对冷轧薄板深冲性能的影响。结果表明，采用低温卷取有利于提高钢板的深冲性能。以3．5mm厚和2．5mm厚热轧板为原料的冷轧低碳钢板的r值分别在冷轧压下率为70．2％和71．3％时出现峰值。生产厚度大于等于0．8mm的低碳钢板时应采用3．5mm厚的热轧卷，生产厚度小于0．8mm的冷轧板时应采用2．5mm厚的热轧卷。     

热轧和卷取温度对IF钢织构的影响

借助三维取向分布函数(ODF)研究了热轧温度、卷取温度对IF钢织构的影响。实验结果表明,IF钢带钢厚度方向表层、1/4厚度处、1/2厚度处的主织构均为{001}<110>。该织构平均密度随F0机架入口带钢温度升高而明显降低,在850℃出现略微升高现象;随F6机架出口带钢温度升高而降低,在834℃出现明显升高后又降低的现象;随卷取温度的升高明显提高。     

Effect of annealing temperature on microstructure,texture and properties of molybdenum foil

The microstructure, texture and mechanical properties of 0.06 mm thick molybdenum foil after annealing at different temperatures were studied by micrograph and EBSD analysis. The results show that the grains of the cold-rolled molybdenum foil along the rolling direction are fibrous. As the annealing temperature increasing from 750 °C to 1000 °C, the average layer thickness of these fibrous grains gradually grows. And the relative frequency of low-angle grain boundaries increases, while the relative frequency of high-angle grain boundaries decreases. Also, the main texture of the unidirectional-rolled and annealed molybdenum foils is {112}〈110〉 which content continuously increase to 62% till 1000 °C. Therefore, the strength of RD, TD and 45°RD direction decreases but the elongation increases. During these processes, the mechanism includes classical nucleation and coarsening of subgrain and with annealing temperature rising, the latter dominates the recrystallization process. After annealing at 1050 °C, the molybdenum foil undergoes secondary recrystallization. The grain boundary distribution becomes diffused and the main texture changes into {001}〈110〉, which the fraction is as high as 96%, thus, the mechanical properties of RD, TD and 45°RD exhibit sharp decrease simultaneously.     

低温取向硅钢热轧析出物与织构的研究

采用低温板坯加热制备取向硅钢,通过透射电镜(TEM)观察并研究热轧板中的析出物,用ODF织构法研究热轧板距表面1/8、1/4和1/2处的织构分布.结果表明,热轧板中的析出物主要是密排六方AlN,AlN形貌呈规则长方形,AlN颗粒大小不等,分布密度低;热轧板中的织构沿板厚方向,由亚表层的{110}＜001＞织构向1/2中...     

Effect of large strain cross rolling on microstructure and properties of Al−Li alloy plates with high magnesium content

Transmission electron microscopy (TEM), electron backscattered diffraction imaging (EBSD) and X-ray diffractometry were used to analyze the microstructure and texture characteristics of Al?9.8Mg?1.5Li?0.4Mn alloy cross-rolled and extruded plates, and the tensile properties and deep drawing performance were measured. The results show that the occurrence of dynamic recrystallization was promoted, the grains were refined and the preferred orientation of the recrystallized grains was improved by large strain cross rolling. Compared with CBA and CCB rolling methods, CBB rolling method significantly reduced the orientation density of the typical Brass texture {110}〈112〉 in the extruded plates. The orientation densities of Copper texture {112}〈111〉 and Brass texture {110}〈112〉 on the β orientation line in the CBB rolled plates were the lowest, and there were no typical texture features in the plates. Meanwhile, better deep drawing could be gained in the CBB rolled plates, and the mechanical properties of the 0°, 45° and 90° directions were basically the same. The tensile strength, yield strength and elongation at room temperature for the CBB rolled plates were 617 MPa, 523 MPa and over 20.1%, respectively. The deviation of the mechanical properties at different directions was less than 3%.     

热轧后退火工序对409L钢带表面起皱的影响

研究了热轧409L铁素体不锈钢钢带在不经退火直接酸洗冷轧和经罩式炉退火后再酸洗冷轧、最后冲压成制品的两种工艺过程中，制品表面的起皱情况，以及各个工序中钢带的金相组织、力学性能和织构，结果表明，利用罩式炉退火工艺生产的最终冷轧退火钢带中平行于轧制面的{111}面织构充分发达、{001}面织构被削弱，材料的抗起皱性较好、轧向r值较高，拉伸或深冲时表面不易产生平行于轧制方向的狭窄条纹起皱缺陷。     

热轧低碳铝镇静钢表层粗晶缺陷原因分析及控制措施

针对低碳铝镇静钢热轧带钢生产时易出现表层粗晶缺陷的问题,对缺陷形貌及分布情况进行了分析,结合该钢种的CCT曲线及轧线实际生产工艺参数,研究了其表层粗晶的产生原因。结果表明,带钢边部温降导致其处于两相区轧制是造成表层粗晶的关键因素。因此,通过提高终轧温度,加强轧线冷却均匀性控制,对轧辊辊身温度监控,精轧采用升速轧制等措施,可以改善带钢长度方向的温度均匀性、减少带钢边部温降,避免带钢进入两相区轧制,可有效控制带钢表层粗晶缺陷。