微碳深冲钢板非{111}织构的形成过程

结合实际生产,采用金相分析、织构测量和透射电镜等方法,研究了微碳深冲钢板中出现的非{111}织构在钢板再结晶时的形成过程,并分析了非{111}织构与冷轧压下率和析出物的关系。研究结果表明：非{111}织构在冷轧变形后即已形成,冷轧压下率较小时,非{111}织构组分相对{111}织构较强;冷轧组织中存在的非{111}取向晶粒在退火过程中会优先成核和优先生长;非{111}织构的形成对AlN的析出不敏感。     

冷轧压下率和罩式退火升温速度对微碳深冲钢板织构的影响

在四辊冷轧试验机和Gleeble-1500试验机上进行了热轧微碳钢板的冷轧和退火试验。用D/max-RC衍射仪测量了试样的1／4层织构，并用Roe软件进行了ODF分析。研究表明，所研究的热轧微碳深冲板压下率约为75％，退火升温速度为20－40℃/h时，试样为{111}织构特征；压下率较大（80％）时，退火织构为较弱的{111}组分。无论{111}织构还是非{111}织构都是在形核阶段开始形成，在晶粒长大优先长大，受到定向形核和选择生长双重机制的作用。     

微碳深冲钢板非{111}织构的定量化表征

对生产试制的一批微碳深冲钢板制成织构试样,在D/max-RC衍射仪上采集测试面的不完整极图,然后由Roe系统ODF织构分析软件绘制ODF图。分析发现,这批钢板的织构均不是典型的{111}织构特征,而是独特的非{111}织构特征。该非{111}织构在ODF图中主要体现为两条螺旋取向线和3条直取向线,对此织构特征进行了分析和定量化表征。     

热轧钢板固溶元素析出对冷轧织构的影响

将热轧钢板在不同温度保温处理析出固溶元素后,在实验室四辊冷轧机上进行轧制,通过透射电镜观察（TEM）和三维取向分析（ODF）,研究了热轧钢板中固溶元素的析出对冷轧织构的影响。结果表明：热轧钢板经700℃和1000℃保温处理后,其冷轧织构仍保持了非{111}织构特征;热轧板中固溶元素析出为二相粒子,有利于冷轧织构中{111}组分的增强,进而具有抑制非{111}织构组分的作用。     

冷轧压下率对含磷深冲钢板织构及深冲性能的影响

利用ODF技术及织构定量技术详细分析了含磷深冲钢板的形变织构和再结晶织构,探讨了冷轧压下率(ε)对钢板织构和深冲性能(r_m,△r)的影响,结果表明,磷钢随着ε的增加,再结晶织构中{111}<112>(包括{554}<225>)织构组分的体积百分比含量增加,同时轧向在晶体学空间的分布更加漫散,从而导致r_m值提高而△r值降低。     

关于深冲薄板退火过程中的再结晶机制问题

为了满足汽车工业的生产需要,鞍钢研制了高强度含磷深冲汽车薄钢板.通过退火时的再结晶使这类钢板中形成{111}类型织构,是保证钢板获得良好深冲性能的首要条件.为此,作者综述了国内外发表的大量有关文献.本文主要叙述这类钢板中的再结晶成核机制、第二相颗粒的影响及晶界迁移问题,有关影响{111}织构形成的一些因素,将在另一篇文章里叙述.     

冷轧压下率对连续退火Ti-IF钢组织和织构的影响

以工业生产的Ti-IF钢热轧板为研究材料,结合连续热镀锌线的工艺特点,采用实验室冷轧、盐浴退火方法和金相、X射线织构测试等分析手段,研究了冷轧压下率对组织和织构的影响规律。试验结果表明,随着冷轧压下率从60%提高到90%,冷轧态α取向线上的取向密度不断增强,而且主要形成了{223}110和{114}110织构,γ线上的{111}110和{111}112织构亦有所增强;退火后铁素体晶粒尺寸从9.0级细化到10.5级;试验钢退火后仍具有较强的{223}110和{114}110织构,且随着冷轧压下率的提高,{111}织构有增强的趋势。要获得强的{111}织构,冷轧压下率需在80%以上。     

关于低碳深冲钢板中{111}织构的形成机制问题（一）

低碳深冲汽车钢板冷轧后退火过程中{111}类型织构的形成受许多因素的影响,其形成机制很复杂。本文就此问题综述国内外的研究成果,主要内容有:①间隙固溶原子碳及氮的影响;②置换固溶原子Mn、P及Si的作用;③原子集团及原子对的效应及第二相的影响;④低碳钢板中再结晶织构与形变织构之间的关系;⑤对今后工作的展望等。本期发表前两部分内容.     

济钢ASP线Ti-IF钢析出相及织构演变分析

采用化学相分析及透射电镜(TEM),对ASP线生产的Ti-IF钢析出相进行了定性和定量的研究,并利用ODF分析方法,揭示了生产过程中Ti-IF钢的织构演变规律.结果表明:析出相主要由TiN、Ti2CS、Ti(C,N)和FeTiP粒子组成.热轧后即发现少量FeTiP粒子,呈球状或椭球状,大小在100nm以下.冷轧过程是深冲织构{111}<110>和{111}<112>形成的重要阶段.冷轧织构由较强的α和γ纤维织构组成.退火过程中,γ织构不断增强同时伴随着α织构的不断减弱,最终形成了沿γ纤维的{111}再结晶织构.     

含氮量对于冷轧低碳沸腾钢板深冲性能的影响

在沸腾钢板的生产中,如果用HNX气体(纯H_2和N_2组成的混合气体)作退火气氛,钢板的含氮量在罩式炉退火阶段就会聚到一个恒定不变的水平。因此,炼钢时增加的含氮量并不影响钢板的应变时效特性,但却恶化了钢板的深冲性能或γ值。为了弄清楚氮对再结晶织构形成的影响,利用在350℃到400℃时铁与气体的反应来改变冷轧和再结晶退火期间钢中的氮含量,然后比较了它们的再结晶织构。再结晶织构中{111)和{110}组份的数量,明显地受退火阶段钢的含氮量的影响,而不受冷轧阶段钢的含氮量的影响,同时,{100}组份的数量或再结晶晶粒度都不受含氮量的影响。这意味着,在炼钢时钢包内大量的氮导致它们以间隙溶质的形式,存在于冷轧钢的回复或再结晶阶段,它们在再结晶退火中促使{110}组份的再结晶而抑制{111}组份的发展。     

Evolution of Through-Thickness Texture in Ultra Purified 17%Cr Ferritic Stainless Steels

 Texture inhomogeneity usually takes place in ferritic stainless steels due to the lack of phase transformation and recrystallization during hot strip rolling, which can deteriorate the formability of final sheets. In order to work out the way of weakening texture inhomogeneity, conventional hot rolling and warm rolling processes have been carried out with an ultra purified ferritic stainless steel. The results showed that the evolution of through-thickness texture is closely dependent on rolling process, especially for the texture in the center layer. For both conventional and warm rolling processes, shear texture components were formed in the surface layers after hot rolling and annealing; sharp α-fiber and weak γ-fiber with the major component at {111}<110> were developed in both cold rolled sheet surfaces, leading to the formation of inhomogeneous γ-fiber dominated by {111}<112> after recrystallization annealing. In the center layer of conventional rolled and annealed bands, strong α-fiber and weak γ-fiber textures were formed; the cold rolled textures were comprised of sharp α-fiber and weak γ-fiber with the major component at {111}<110>, and inhomogeneous γ-fiber dominated by {111}<112> was formed after recrystallization annealing. By contrast, in the centre layer of warm rolled bands, the texture was comprised of weak α-fiber and sharp γ-fiber, and γ-fiber became the only component after annealing. The cold rolled texture displayed a sharp γ-fiber with the major component at {111}<112> and the intensity of γ-fiber close to that of α-fiber, resulting in the formation of a nearly homogeneous γ-fiber recrystallization texture in the center layer of the final sheet.     

摩擦对IF钢铁素体区热轧和退火织构的影响

采用X射线衍射仪分析IF钢铁素体区热轧织构以及退火织构的演化,在实验室热轧机上进行了IF钢的铁素体区热轧,研究了摩擦对IF钢铁素体区热轧、退火织构的影响。结果表明：无润滑轧制时,钢板表层形成强高斯织构组分{110}〈001〉,弱γ纤维织构,导致再结晶织构中高斯组分强度高,γ纤维织构强度低;润滑轧制时,钢板表层高斯织构组分强度降低,{100}〈011〉、γ纤维织构强度提高,退火后γ纤维织构强度提高。钢板中心受摩擦作用影响较小,轧制过程中发展为较强的α和γ纤维织构,退火后γ纤维织构成为主要织构组分。     

Effects of Rolling Parameters on Texture and Formability of High Strength Ultra-Low Carbon BH Steel

 The effects of hot rolling and cold rolling parameters on texture and r (plastic strain ratio) value of high strength ultra low carbon bake hardening (ULC-BH) steels are studied with orientation distribution function (ODF) structural analysis method. After hot rolling, the high strength ULC-BH steel sheet has weak γ-fiber with uniform orientation distributions, and weak α-fiber, of which {445}<110> component forms a high intensity peak at coiling temperature of 750 ℃. After cold rolling, both {111}<110>-{111}<112> intensity on the γ-fiber and {111}-{112}<110> intensity on the α-fiber enhanced. As a result of substitutional solute elements Mn and P being added to the steel, strong {112}<110> deformation texture component is observed on α-fiber, especially at 80% cold rolling reduction, and this leads to the strong {111}<112> recrystallization texture after annealing. The increase of cold rolling reduction shifts the maximum intensity on the γ-fiber from {111}<112> to {111}<113>. After annealing, a very strong γ-fiber is obtained, with intensity peak at {111}<112> component when cold rolling reduction reaches 80%. Increasing coiling temperature and cold rolling reduction improve γ-fiber intensity and r value, resulting in good deep drawability.     

Texture of Cold Rolled Strip of Fe-3Si Steel Produced by Thin Slab Casting and Rolling

 The hot rolled strip of Fe-3Si steel was experimentally produced by thin slab casting and rolling (TSCR) process in the laboratory. The texture evolution rule was investigated during hot rolling and cold rolling. The texture distribution of cold rolled strips with four kinds of cold rolling reduction schedules was observed through X-ray diffraction method, and the orientation density variation of 1/16 layer, 1/8 layer, 1/4 layer, and 1/2 layer in thickness was analyzed. The cold rolled texture of steel A with four kinds of cold rolling reduction schedules was mainly composed of α and γ fibers. Cold rolling reduction ratio of 70% was more beneficial for obtaining more γ fibers. The γ fiber texture orientation density of {111}<011> and {111}<1 12> was the largest on the 1/8 layer and 1/4 layer and the least on the 1/16 layer and 1/2 layer for steel B. The texture orientation density of {001}-{223}<110> in the α fibers for steel C was increased, but the texture orientation density of {332}-{110}<110> was low.     

冷轧压下率对无抑制剂取向硅钢初次再结晶退火的影响

对无抑制剂取向硅钢不同压下率下初次再结晶退火后的显微组织、宏观织构和微观织构进行了研究.结果表明,冷轧板织构主要为α取向线{001}＜110＞、{112}＜110＞和{111}＜110＞织构以及γ取向线{111}＜110＞织构.初次再结晶退火后,α取向线织构减弱,织构主要为γ取向线{111}＜112＞织构.随冷轧压下率的增加,冷轧和初次再结晶织构强度增加.当压下率为88％时,初次再结晶退火后 Goss 织构和{111}＜112＞织构强度最高,最有利于发生二次再结晶.EBSD 分析显示,Goss 取向晶粒大多与{111}＜112＞取向晶粒相邻.提高冷轧压下率,Goss取向晶粒和{111}＜112＞取向晶粒都增加,Goss 取向晶粒偏离理想取向角度减少.     

430不锈钢冷轧板高温退火过程中再结晶织构的定量分析

在750、800、825和850℃温度下,利用Gleeble1500热模拟试验机对430不锈钢冷轧薄板的等温退火过程进行了详细的实验研究,分析了退火过程中再结晶织构和组织的变化规律,并对关键织构体积分数的演变进行了定量分析.结果发现:随着退火过程的进行,α取向线上的织构强度逐渐减弱,而γ取向线上的织构强度则略有加强,并保持在较高的值;再结晶过程中,{111}和{112}<110>织构的体积分数逐渐降低,而{100}和随机取向晶粒的体积分数逐渐增加.定量分析表明,退火温度越低,完全再结晶后材料内部关键织构的体积分数越偏离冷轧态.最后,针对{111}、{112}<110>、{100}和随机取向织构的体积分数在再结晶过程中的演变规律,建立了JMAK型再结晶织构演变动力学模型.      

Effect of Processing Condition on Texture and Drawability of a Ferritic Rolled and Annealed Interstitial-Free Steel

The processing conditions of the texture formation and deep drawability of a Ti-IF steel strip hot-rolled in ferritic region and subsequently annealed were investigated. The r-value increases with the decrease of reheating temperature, and finish rolling temperature and the increase of reductions in ferritic region. For lubricated ferritic rolling and annealing, the r-value is raised up to 1.75, and elongation rate is over 50% at the finish rolling temperature of 650 ℃, which is suitable for DDQ grade products. However, the r-value is below 1.0 in the case of unlubricated rolling. The X-ray diffraction was used to analyze the textural characteristic of samples. For samples subjected to lubricated rolling and annealing, the strong { 111 }//ND recrystallization texture is distributed homogeneously along the thickness direction, and the intensity of { 110} recrystallization texture is very low even in surface. However, for unlubricated samples, the {111} texture is distributed inhomogeneously and is weak along the thickness direction, and （110}//ND recrystallization texture is strong, which deteriorates the formability.