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4不锈钢-碳钢复合板多道次小变形轧制温度场的数值模拟 总被引:1,自引:0,他引:1
基于弹塑性热力耦合有限元法研究了72mm Q235钢基板和14mm 304不锈钢复板11道次变形至12mm复合板的热轧过程,并应用有限元MARC软件二次开发技术建立了温度场模型。模拟结果表明,变形区内,复合板表面温度持续下降,界面温度略有升高;变形区外,表面温度有所回升;随轧制过程进行,轧件高度方向温度梯度逐渐减小;界面处温度呈“S”形,变形区温度变化显著,且随轧制速度提高,升温明显。 相似文献
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不锈钢/碳钢复合板既发挥了不锈钢的强耐腐蚀性、高耐磨性、高耐热性和高磁性,又结合了碳钢的易焊接性、高导热性和易延展性等优势。然而,不锈钢/碳钢复合板较低的结合强度严重限制了其广泛的应用。提出采用纵波轧制(LCR)制备不锈钢/碳钢复合板的工艺,从试验和有限元模拟2个方面研究了变形过程中搓轧区对复合板结合强度的影响,并与平辊轧制(FR)工艺进行对比。结果表明,LCR复合板在波峰和波谷处的拉剪强度分别为315.94 MPa和329.48 MPa, FR复合板的拉剪强度为277.77 MPa。波峰和波谷处的拉剪强度较FR复合板分别提升了13.7%和18.6%。通过对拉剪断裂面进行元素扫描分析发现,LCR复合板波峰和波谷的断裂位置处于Q235B基体中,FR复合板的断裂位置在结合界面上。LCR复合板的拉伸强度和断后伸长率均优于FR复合板。利用有限元模拟获得LCR和FR变形区复合板的应力状态分布,LCR变形区中部分金属处于两向压应力和一向拉应力状态,应力状态更接近纯剪状态,LCR复合板在轧制过程中受到拉应力和强烈的剪应力共同作用。与FR变形区不同,LCR变形区由于波纹辊型的影响,在轧制方向和宽度方向... 相似文献
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介绍了碳扩散对SUS304+Q235B复合板卷轧制结合性能的影响。热轧过程中SUS304+Q235B不锈钢复合板卷基覆层间碳扩散,主要发生在卷取后较长时间的缓慢冷却过程中。结合界面碳元素的大量扩散,使界面不锈钢侧碳含量大幅度提高,增加了在敏化温度下铬的碳化物析出,导致覆层侧不锈钢塑性降低和脆性增加。基层侧碳钢脱碳后,结合面基层侧的铁素体数量增加,塑性改善增强,使结合面附近基层与覆层的塑性变形能力差距增大,破坏基层与覆层间结合界面变形协调性,减弱结合面的结合强度。退火加速基覆层间碳的扩散,但固溶处理方式可以继续保持热轧态的基覆层间碳扩散的状况。 相似文献
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为了研究真空热轧不锈钢复合板的结合行为,本文以热轧304不锈钢/Q345低碳钢复合板为研究对象,通过剪切试验及组织分析等手段研究了变形量及真空度对不锈钢复合板结合性能的影响规律.结果表明,轧制总变形量从35%增加到75%之后复合板的剪切强度大约可增加100 MPa.真空度降低会导致结合界面氧化程度增加,进而降低复合板的结合性能,当真空由0.1 Pa变为20 Pa时,界面氧化物的比例由约10%提高到约50%,剪切强度由440 MPa降低到了350 MPa左右.最后根据试验结果提出了热轧不锈钢复合板的结合行为. 相似文献
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采用对称组坯的方式,热轧法生产304+Q235B不锈钢复合板,在热轧完成后,对自然空冷和ACC冷却的两种钢板取样进行检测分析,对比两种冷却条件下304不锈钢晶间腐蚀的情况。结果表明,在ACC冷却条件下,复合板表面不锈钢未产生晶间腐蚀。 相似文献
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为确定制备316L/EH40不锈钢复合板所需压下率,采用MSC.Marc有限元软件模拟研究了316L/EH40不锈钢复合板在不同压下率下的轧制过程,通过对变形区结合界面处应力场与应变场的综合分析,确定不锈钢复合板实现有效黏合的最小压下率为55%。基于有限元仿真结果,采用Gleeble-3800热模拟试验机制备了不同变形率下的复合样件,并对复合样件结合界面处的微观组织形貌进行了观测。通过分析得出结论,样件压下率达到30%后,结合界面处孔隙基本闭合,但仍有部分夹杂物和微孔存在;当压下率超过50%后,结合界面处微孔完全消失,夹杂物数量减少并且尺寸减小;低合金钢侧组织由铁素体和珠光体组成,靠近结合面处存在脱碳层,随着压下率的提高,脱碳层厚度逐渐降低;不锈钢侧由奥氏体组织组成,奥氏体晶粒尺寸随着压下率的提高得到不同程度的细化;显微硬度值随着压下率提高逐渐增大。 相似文献
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通过“爆炸+轧制”法生产的0.80~1.20mm的304不锈钢碳钢(Q235A,08Al)304不锈钢复合板的厚度比例为1∶10∶1,该板在建筑门窗幕墙和日用炊具领域有广泛应用前景。冷弯试样产生裂纹的分析结果表明,基板含碳量高的Q235A钢(0.16%C)比基板含碳量低的08Al钢(0.06%C)出现裂纹的几率大,并且钢中夹杂物、钢的晶粒度和热处理工艺均影响冷轧复合板的弯曲性能。通过选择08Al钢为基层板,控制1050℃热处理工艺,使晶粒度级别≤8级,可明显改善冷轧复合钢板的弯曲性能。 相似文献
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用MMS-200热模拟实验机对2507超级双相不锈钢(/%:0.022C、0.58Si、25.35Cr、7.17Ni、4.05Mo、0.28N)12 mm热轧板在1 000~1150℃、应变速率0.01~10s-1下进行了热压缩实验。实验结果表明,在应变速率一定的条件下,变形温度越高,2507超级双相不锈钢峰值应力越低;在变形温度一定的条件下,峰值应力随着应变速率的增加而增加。根据热变形方程计算得到压缩变形时的平均表观应力指数n=3.25,热变形激活能Q=460kJ/mol。基于实验数据构建了2507超级双相不锈钢在相应变形条件下的热变形方程。 相似文献
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介绍了轧制法生产不锈钢复合板的技术,并以304不锈钢和Q345R两者复合轧制为例,分析了采用该方法生产复合钢板的力学性能及复合界面组织形貌结构特征。结果表明,采用轧制法生产不锈钢复合钢板结合面无锯齿形,基层、复层组织均良好,板材拉伸断口无分层及白斑,力学性能完全满足不锈钢复合板的要求。 相似文献
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为了获得桥梁用不锈钢复合板良好的综合性能,采用控轧控冷(thermal mechanical control process,简称TMCP)工艺轧制了桥梁用不锈钢复合板316L+Q370qD,利用金相、扫描、拉伸、冲击、弯曲、剪切和晶间腐蚀等手段研究了该复合板的组织与性能。结果表明,316L+Q370qD桥梁用不锈钢复合板的界面实现了完全冶金结合,未发现孔洞、裂纹等缺陷以及大颗粒的析出物及氧化物夹杂等;复合板的屈服强度为421~446MPa,伸长率为24.0%~28.0%,-20℃纵向冲击吸收能量平均值为200J,180°内、外弯曲合格,平均剪切强度为412 MPa,复合板的各项力学性能均满足GB/T 8165—2008《不锈钢复合钢板和钢带》标准要求。按照GB/T 4334—2008方法 E进行晶间腐蚀试验,复层不锈钢316L未出现晶间腐蚀现象,具有良好的耐晶间腐蚀性能。 相似文献
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The stress states developed during room temperature, plane strain compression modes of deformation of stainless steel clad
aluminum and aluminum clad strainless steel sheets have been investigated in order to gain insight into the formability of
bonded ductile sandwich sheet materials in primary metalworking processes. Assuming uniform, isostrain deformation in the
component layers, sandwich compression stress-strain curves were predicted to be rule of mixtures averages of component compression
stress-strain curves. These predictions showed good agreement with experimental data when friction and in-homogeneous deformation
were taken into account. Since the through-thickness applied pressure can be assumed to be the same in both components of
thin sandwich sheet materials, in-plane stresses which are tensile in the harder component and compressive in the softer component
of a clad sheet are developed in order to satisfy the yield conditions. The nature of these in-plane stresses was confirmed
by measurements of residual stress distributions in rolled clad sheet specimens, and it was shown how the tensile stress in
the harder component may lead to unstable flow and failure of this component during forming. The observed failures were similar
in both plane-strain indentation and rolling tests. Although the initiation of instability in symmetric clad sheet metals
appears to be independent of the arrangement of the component layers, the process of final localization leading to fracture
was observed to depend heavily on the layer arrangement.
S. L. SEMIATIN, formerly Graduate Student, Department of Metallurgy and Materials Science, Carnegie-Mellon University. 相似文献
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为了研究推/张力(0~15 MPa)对不锈钢(Cr18Ni8,2 mm壁厚管)/碳钢(0.06%~0.12%C,Φ16 mm,圆棒)复合钢筋轧制过程的影响,应用有限元软件Msc.Marc建立了复合钢筋轧制过程的有限元模型。通过模拟考察了推/张力对不锈钢/碳钢复合钢筋的宽展变形,结合面的接触应力和不锈钢圆周壁厚的影响,重点通过实验考察了推力轧制对两金属结合强度的影响。结果表明,施加张力后轧件宽展量减小,而施加推力后其值增加;不锈钢壳与碳钢芯间的接触应力随推力的增加、张力的降低而增大。推力轧制有利于两金属的复合,可以提高复合不锈钢和碳钢芯的结合强度。 相似文献
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The stable and unstable plastic flow of stainless steel-clad aluminum and aluminum-clad stainless steel sandwich sheet materials
deformed in uniaxial tension have been investigated. For the clad sheet materials studied experimentally, stable deformations
were uniform in the component layers, and the assumption of isostrain was used in modeling the deformation behavior. The rule
of mixtures, an average of component properties weighted by cross-sectional area fractions, was applied to determine sandwich
uniaxial true stress-true strain curves from those of the components. In addition, measurements of residual stress distributions
in deformed tensile specimens gave insight into states of stress during loading. A model to determine the magnitude of stresses
which are generated by component normal plastic anisotropy differences was developed as well. With this knowledge of the stress
state, predictions of uniform elongation of the clad sheet materials were made which compared favorably to experimental measurements.
As for ductile monolithic sheet materials, stable flow of sandwich sheet materials in tension was limited by diffuse necking,
which leads to local instability at higher strains. This local instability gives rise to a through-thickness localized thinning
which terminates macroscopic deformation. Conditions for local instability in uniaxial tension have been developed for sandwich
as well as monolithic sheet materials. Predictions from these models are in agreement with measurements.
S. L. SEMIATIN, forMetly Graduate Student, Department of Metal-lurgy and Materials Science, Carnegie-Mellon University. 相似文献